DNV-RU-SHIP Pt.5 Ch.1 Bulk carriers and dry cargo ships

RULES FOR CLASSIFICATION

Ships

Edition July 2021

Part 5 Ship types

Chapter 1 Bulk carriers and dry cargo ships

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FOREWORD

DNV rules for classification contain procedural and technical requirements related to obtaining andretaining a class certificate. The rules represent all requirements adopted by the Society as basisfor classification.

© DNV AS July 2021

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CHANGES – CURRENT

This document supersedes the July 2020 edition of DNVGL-RU-SHIP Pt.5 Ch.1.The numbering and/or title of items containing changes is highlighted in red.

Changes July 2021, entering into force 1 January 2022

Topic Reference Description

Guidance for ship typenotation application

Sec.1 [2.1] Clarification of ship types for ships carrying dry bulk cargo

Documentation requirements Sec.1 [4.1.1] Documentation requirements for general dry cargo ship, multi-purpose dry cargo ship, bulk carrier and ore carrier are mergedinto one table.

Compliance documents Sec.1 [5.1.1] Compliance documents for general dry cargo ship, multi-purpose dry cargo ship, bulk carrier and ore carrier are mergedinto one table.

Rearrangement of contents Sec.2, Sec.5, Sec.6,Sec.7

Common requirements related to carriage of dry cargoes inbulk are moved to Sec.2 from Sec.5, Sec.6, and Sec.7.

FE fatigue assessment Sec.2 [3.5.1] In FE fatigue assessment, bulk cargo shear loads shall beincluded.

Corrugation span Sec.4 [3.2.3] The definition of corrugation span is clarified.

Loading pattern Sec.5 [4.2.6] Loading pattern for ships with 2 to 4 cargo holds are clarified,taking loading in blocks into consideration.

Hold mass curves Sec.9 [4.4] Hold mass curves for ships sailing in the Great Lakes areclarified.

Rebranding to DNV All This document has been revised due to the rebranding of DNVGL to DNV. The following have been updated: the companyname, material and certificate designations, and references toother documents in the DNV portfolio. Some of the documentsreferred to may not yet have been rebranded. If so, please seethe relevant DNV GL document.

Editorial correctionsIn addition to the above stated changes, editorial corrections may have been made.

Part 5 Chapter 1 Changes - current

Rules for classification: Ships — DNV-RU-SHIP Pt.5 Ch.1. Edition July 2021 Bulk carriers and dry cargo ships

DNV AS

CONTENTS

Changes – current.................................................................................................. 3

Section 1 General..................................................................................................111 Introduction.......................................................................................111.1 Introduction................................................................................... 111.2 Scope............................................................................................ 111.3 Application..................................................................................... 11

2 Class notations.................................................................................. 112.1 Ship type notations.........................................................................112.2 Additional notations........................................................................ 13

3 Definitions..........................................................................................143.1 Terms............................................................................................ 14

4 Documentation...................................................................................144.1 Documentation requirements............................................................14

5 Compliance documentation................................................................155.1 Required compliance documentation..................................................15

6 Testing...............................................................................................166.1 Testing during newbuilding...............................................................16

Section 2 Common requirements.......................................................................... 171 Introduction.......................................................................................191.1 Introduction................................................................................... 191.2 Scope............................................................................................ 191.3 Application..................................................................................... 19

2 Structural design principles...............................................................192.1 Structural arrangement - double side structure...................................192.2 Structural arrangement - single side structure....................................202.3 Structural arrangement - deck structure............................................ 212.4 Structural arrangement - plane bulkheads......................................... 232.5 Detailed design...............................................................................23

3 Pressures and forces due to dry bulk cargo.......................................233.1 Application..................................................................................... 233.2 Hold definitions...............................................................................233.3 Dry cargo characteristics................................................................. 253.4 Dry bulk cargo pressures.................................................................323.5 Shear load..................................................................................... 32

4 Design load scenarios........................................................................33

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4.1 General..........................................................................................334.2 Additional principal design load scenarios for dry cargo ships................34

5 Hull local scantling............................................................................ 365.1 Design load sets for ships intended to carry dry bulk cargo.................. 365.2 Cargo hold side frames of single side skin construction........................ 40

6 Additional safety measures for ships intended to carry dry cargo inbulk.......................................................................................................416.1 Application..................................................................................... 416.2 Corrosion protection of double side spaces.........................................426.3 Enhanced flooded requirements........................................................ 426.4 Double side configuration.................................................................426.5 Protection against loading/discharge equipment..................................436.6 Single failure of cargo hold structures............................................... 436.7 Information on compliance with requirements.................................... 43

7 Additional safety measures for ships with class notation ESP............447.1 Application..................................................................................... 447.2 Access to and within spaces in, and forward of, the cargo area..............447.3 Free-fall lifeboat............................................................................. 447.4 Forecastle...................................................................................... 447.5 Corrosion protection of cargo hold spaces.......................................... 447.6 Single side structure....................................................................... 447.7 Cargo hatch covers and hatch coamings............................................ 44

8 Water ingress alarms and drainage of forward spaces...................... 448.1 Water ingress alarms in single hold dry cargo ships.............................448.2 Water ingress alarms in dry cargo ships carrying dry cargo in bulk.........458.3 Availability of pumping systems........................................................46

Section 3 Steel coil requirements......................................................................... 471 Introduction.......................................................................................481.1 Introduction................................................................................... 481.2 Scope............................................................................................ 481.3 Application..................................................................................... 48

2 Steel coil loads in cargo holds...........................................................482.1 General..........................................................................................482.2 Total loads..................................................................................... 512.3 Static loads....................................................................................522.4 Dynamic loads................................................................................53

3 Hull local scantling............................................................................ 533.1 General..........................................................................................53



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3.2 Load application..............................................................................543.3 Inner bottom..................................................................................543.4 Hopper tank and inner hull.............................................................. 55

Section 4 Enhanced flooded requirements............................................................ 571 Introduction.......................................................................................571.1 Introduction................................................................................... 571.2 Scope............................................................................................ 571.3 Application..................................................................................... 58

2 Hull girder loads, pressures and forces due to dry cargoes inflooded conditions................................................................................ 582.1 Vertical still water hull girder loads................................................... 582.2 Vertically corrugated transverse watertight bulkheads..........................582.3 Double bottom in cargo hold region in flooded conditions..................... 64

3 Transverse vertically corrugated watertight bulkheads separatingcargo holds in flooded condition.......................................................... 653.1 Structural arrangement....................................................................653.2 Net thickness of corrugation............................................................ 663.3 Bending, shear and buckling check................................................... 683.4 Net section modulus at the lower end of the corrugations.................... 693.5 Supporting structure in way of corrugated bulkheads...........................723.6 Upper and lower stool subject to lateral flooded pressure..................... 733.7 Corrosion addition...........................................................................73

4 Allowable hold loading in flooded conditions.....................................734.1 Evaluation of double bottom capacity and allowable hold loading........... 73

5 Vertical hull girder bending and shear strength in floodedconditions............................................................................................. 775.1 Vertical hull girder bending strength..................................................775.2 Vertical hull girder shear strength of bulk carriers............................... 785.3 Vertical hull girder shear strength of ore carriers................................ 785.4 Hull girder ultimate strength check................................................... 79

Section 5 General dry cargo ships and multi-purpose dry cargo ships.................. 801 Introduction.......................................................................................811.1 Introduction................................................................................... 811.2 Scope............................................................................................ 811.3 Application..................................................................................... 81

2 General arrangement design............................................................. 812.1 General..........................................................................................812.2 Occasional carriage of dry cargoes in bulk......................................... 81



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3 Structural design principles...............................................................823.1 General..........................................................................................82

4 Loads................................................................................................. 824.1 Standard design loading conditions................................................... 824.2 Loading conditions for primary supporting members............................83

5 Hull girder strength........................................................................... 915.1 Vertical hull girder bending strength..................................................915.2 Vertical hull girder shear strength.....................................................915.3 Loading instrument......................................................................... 93

6 Hull local scantling............................................................................ 946.1 Plating........................................................................................... 946.2 Stiffeners....................................................................................... 946.3 Primary supporting members........................................................... 946.4 Intersection of stiffeners and primary supporting members.................. 946.5 Fixed cargo securing devices............................................................94

7 Finite element analysis......................................................................957.1 General..........................................................................................957.2 Cargo hold analysis.........................................................................957.3 Global strength analysis.................................................................. 977.4 Embedded cargo hold analysis..........................................................97

8 Buckling............................................................................................. 988.1 Hull girder buckling.........................................................................98

9 Fatigue...............................................................................................989.1 General..........................................................................................989.2 Prescriptive fatigue strength assessment........................................... 98

Section 6 Bulk carriers..........................................................................................991 Introduction.......................................................................................991.1 Introduction................................................................................... 991.2 Scope............................................................................................ 991.3 Application..................................................................................... 99

2 CSR and non-CSR bulk carriers........................................................1002.1 CSR Bulk carriers..........................................................................1002.2 Non-CSR Bulk carriers................................................................... 100

Section 7 Ore carriers......................................................................................... 1011 Introduction.....................................................................................1011.1 Introduction..................................................................................1011.2 Scope.......................................................................................... 101



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1.3 Application................................................................................... 1012 General arrangement design........................................................... 1022.1 General........................................................................................102

3 Structural design principles............................................................. 1023.1 General........................................................................................1023.2 Structural arrangement - fore peak structure....................................1023.3 Structural arrangement - machinery space....................................... 103

4 Loads............................................................................................... 1034.1 Standard design loading conditions................................................. 1034.2 Loading conditions for primary supporting members.......................... 104

5 Hull girder strength......................................................................... 1045.1 Vertical hull girder shear strength................................................... 1045.2 Hull girder yield check...................................................................109

6 Hull local scantling.......................................................................... 1116.1 Minimum thickness........................................................................1116.2 Plating......................................................................................... 1116.3 Stiffeners..................................................................................... 1116.4 Primary supporting members..........................................................1126.5 Intersection of stiffeners and primary supporting members.................112

7 Finite element analysis....................................................................1127.1 Cargo hold analysis....................................................................... 112

8 Buckling........................................................................................... 1138.1 Hull girder buckling....................................................................... 113

9 Fatigue.............................................................................................1139.1 General........................................................................................1139.2 Prescriptive fatigue strength assessment..........................................113

Section 8 Ships specialised for the carriage of a single type of dry bulk cargo.... 1141 Introduction.....................................................................................1141.1 Introduction..................................................................................1141.2 Scope.......................................................................................... 1141.3 Application................................................................................... 114

2 General arrangement design........................................................... 1142.1 Compartment arrangement............................................................ 114

3 Structural design principles............................................................. 1153.1 Structural arrangement..................................................................115

4 Loads............................................................................................... 1154.1 Standard design loading conditions................................................. 1154.2 Loading conditions for primary supporting members.......................... 115



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5 Hull girder strength......................................................................... 1155.1 Loading manual and loading instrument...........................................115

6 Hull local scantling.......................................................................... 1156.1 Minimum thickness........................................................................1156.2 Plating......................................................................................... 1166.3 Stiffeners..................................................................................... 1166.4 Primary supporting members..........................................................1166.5 Intersection of stiffeners and primary supporting members.................116

7 Finite element analysis....................................................................1167.1 Cargo hold analysis....................................................................... 116


9 Fatigue.............................................................................................1179.1 General........................................................................................1179.2 Prescriptive fatigue strength assessment..........................................117

Section 9 Great lakes bulk carriers..................................................................... 1181 Introduction.....................................................................................1181.1 Introduction..................................................................................1181.2 Scope.......................................................................................... 1181.3 Application................................................................................... 118

2 General arrangement design........................................................... 1182.1 Subdivision arrangement................................................................118

3 Structural design principles............................................................. 1193.1 Corrosion additions........................................................................1193.2 Structural arrangement..................................................................119

4 Loads............................................................................................... 1194.1 General........................................................................................1194.2 Standard design loading conditions................................................. 1194.3 Loading conditions for primary supporting members.......................... 1194.4 Hold mass curves..........................................................................119

5 Hull girder strength......................................................................... 1205.1 Vertical hull girder shear strength................................................... 1205.2 Hull girder yield check...................................................................1205.3 Hull girder ultimate strength check................................................. 120

6 Hull local scantling.......................................................................... 1206.1 Plating......................................................................................... 1206.2 Stiffeners..................................................................................... 1206.3 Primary supporting members..........................................................120



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6.4 Intersection of stiffeners and primary supporting members.................1207 Finite element analysis....................................................................1217.1 Cargo hold analysis....................................................................... 121


9 Fatigue.............................................................................................1219.1 General........................................................................................121

10 Special requirements..................................................................... 12110.1 Bow impact................................................................................ 12110.2 Bottom slamming........................................................................ 12210.3 Stern slamming...........................................................................122

11 Hull equipment, supporting structures and appendages................ 12211.1 Anchoring and mooring equipment................................................ 12211.2 Supporting structure for deck equipment and fittings....................... 12211.3 Bulwark and protection of crew.....................................................122

12 Openings and closing appliances................................................... 12312.1 General...................................................................................... 12312.2 Small hatchways and weathertight doors........................................12312.3 Cargo hatch covers/coamings and closing arrangements...................12312.4 Side, stern and bow doors/ramps..................................................12412.5 Tank access, ullage and ventilation openings...................................12412.6 Machinery space openings............................................................ 12412.7 Scuppers, inlets and discharges.................................................... 12412.8 Freeing ports.............................................................................. 125

13 Stability..........................................................................................12513.1 General...................................................................................... 125

Changes – historic.............................................................................................. 126



DNV AS

SECTION 1 GENERALSymbolsFor symbols not defined in this section, see Pt.3 Ch.1 Sec.4 [2].

1 Introduction

1.1 IntroductionThese rules apply to ships intended for carriage of various dry cargoes.

1.2 ScopeThe rules in this chapter give requirements for hull strength and equipment, including:

— general requirements given in this section are applicable to all ship types listed in Table 1— common requirements given in Sec.2 are in general applicable to all ship types listed in Table 1. For shipsassigned the ship type notation Bulk carrier (with CSR) only requirements given in Sec.2 [8.2] andSec.2 [8.3] are applicable

— steel coil requirements given in Sec.3 are applicable to all ships, except from Bulk carrier (with CSR),loaded by steel coils on wooden dunnage

— enhanced flooded requirements given in Sec.4 are applicable to ships assigned ship type notation Orecarrier or Bulk carrier (without CSR), complying with criteria further given in Sec.4 [1.3]

— ship type specific requirements are given in Sec.5 to Sec.9 for ship types listed in Table 1.

1.3 ApplicationThe requirements in this chapter are supplementary to those given in Pt.2, Pt.3 and Pt.4 that are applicablefor the assignment of main character of class.

2 Class notations

2.1 Ship type notationsVessels built in compliance with the requirements as specified in Table 1 will be assigned one of the classnotations as follows:

Table 1 Ship type notations

Class notation DescriptionDesign

requirements,rule reference

General dry cargo ship1) carriage of unitized and dry bulk cargo Sec.5

Multi-purpose dry cargo ship2) carriage of unitized and dry bulk cargo Sec.5

Bulk carrier3) carriage of dry bulk cargo Sec.6

Ore carrier4) carriage of ore cargo in dry bulk Sec.7

X carrier5) ships specialised for the carriage of a single type of dry bulkcargo Sec.8

Part 5 Chapter 1 Section 1


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Class notation DescriptionDesign

requirements,rule reference

Great lakes bulk carrier6) carriage of dry bulk cargo Sec.9

1) Mandatory for ships occasionally carrying dry cargo in bulk, unless ship type notation Multi-purpose dry cargoship is assigned.

2) Mandatory for ships occasionally carrying dry cargo in bulk, unless ship type notation General dry cargo ship isassigned.

3) Mandatory for sea-going single deck ships with cargo holds of single and or double side skin construction, with adouble bottom, hopper side tanks and top-wing tanks fitted below the upper deck, and intended for the carriageof solid bulk cargoes. Also mandatory for ships primarily intended for the carriage of solid bulk cargoes with otherstructural arrangements.

4) Mandatory for sea-going single deck ships having two longitudinal bulkheads and a double bottom throughout thecargo region, and intended for carrying ore cargoes in the centre hold only.

5) Mandatory, unless ship type notation Bulk carrier is assigned. X denotes the type of bulk cargo to be carried,limited to either Woodchips, Cement, Fly ash or Sugar.

6) Designed to operate within the limits of the Great Lakes and St. Lawrence river to the seaward limits defined by theAnticosti Island.

Ships intended for the occasional carriage of dry bulk cargo may be assigned with the ship type notationGeneral dry cargo ship or Multi-purpose dry cargo ship.

Guidance note:Ships intended for the occasional carriage of dry bulk cargo will be stated as “other cargo ship” in Cargo Ship Safety ConstructionCertificate (CCC) and Cargo Ship Safety Equipment Certificate (CEC), or Cargo Ship Safety Certificate (CSSC). The requirementsgiven in Sec.5 complies with the provisions set in IMO resolution MSC.277(85) for ships intended for occasional carriage of drycargoes in bulk.

---e-n-d---o-f---g-u-i-d-a-n-c-e---n-o-t-e---

Ships intended for the primary carriage of dry bulk cargo or dry bulk ore cargo may be assigned with theship type notation Bulk carrier or Ore Carrier specificly. For ships with the ship type notation Bulk Carrierwith cross section given in Sec.6 [1.3.2] or Ore carrier, the class notation ESP is mandatory. For ships withthe ship type notation Bulk Carrier with cross section given in Sec.6 [1.3.3], the class notation ESP is notmandatory.

Guidance note:Ships intended for the primary carriage of dry bulk cargo or dry bulk ore cargo will be stated as “bulk carrier” in Cargo Ship SafetyConstruction Certificate (CCC) and Cargo Ship Safety Equipment Certificate (CEC), or Cargo Ship Safety Certificate (CSSC).For ships with the ship type notation Bulk Carrier with cross section given in Sec.6 [1.3.3], a statement of fact will be issued todocument that the vessel is a bulk carrier in compliance with SOLAS Chapter XII, not as defined in SOLAS Chapter IX/1.6 withrespect to SOLAS Chapters IX and XI-2, and not subject to SOLAS II-1/3-6, III/31.1.8, XI-1/2, enhanced surveys.


Ships specialised for the carriage of a single type of dry bulk cargo (woodchips, cement, fly ash or sugar)may be assigned with the ship type notation X carrier.

Guidance note:Ships specialised for the carriage of a single type of dry bulk cargo (woodchips, cement, fly ash or sugar) will be stated as “othercargo ship” in Cargo Ship Safety Construction Certificate (CCC) and Cargo Ship Safety Equipment Certificate (CEC), or Cargo ShipSafety Certificate (CSSC).




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2.2 Additional notations

2.2.1 The following additional notations, as specified in Table 2, are typically applied to dry cargo ships:

Table 2 Additional notations

Class notation Description Application

CSR ships designed and built according to IACS commonstructural rules

mandatory for Bulk carrier with L ≥ 90 m andcross section in accordance with Sec.6 Figure 1

BC strengthened for heavy cargo in bulk mandatory for Bulk carrier (with CSR) with L ≥150 m

Grab strengthened for grab loading and unloading mandatory for ships with:

— LLL ≥ 150 m and bulk density ρc ≥ 1.0 t/m3

— BC(A) or BC(B)— HC(A), HC(B*) or HC(B)— HC(M) with ρc ≥ 1.0 t/m3

— OC(M) or OC(H)

Strengthened strengthened for heavy cargo all ships

HL tanks or holds strengthened for heavy liquid all ships

HC strengthened for heavy cargo in bulk mandatory for:

— General dry cargo ship or Multi-purposedry cargo ship with L ≥ 150 m andminimum five cargo holds

— Bulk carrier (without CSR) with L ≥ 150 m

OC strengthened for ore cargo mandatory for Ore carrier with L ≥ 150 m

RSD extended strength analysis with a global FE-model may be applied to General dry cargo ship andMulti-purpose dry cargo ship

Plus extended fatigue analysis of ship details all ships

CSA direct analysis of ship structures all ships

EL easy loading of cargo holds may be applied to Ore carriers

Container equipped for carriage of containers for ships other than Container ships

Crane crane on board all ships except from Crane vessel

DG arranged for carriage of dangerous goods all ships

SAFELASH increased stevedores’ safety engaged in containerhandling

may be applied to ships with Containernotation

ESP ships subject to an enhanced survey programme mandatory for Ore carriers and Bulk carriersas given in Pt.6 Ch.9 Sec.2

CMON construction monitoring of hull critical locations all ships



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Class notation Description Application

RO/RO designed and arranged for roll-on and roll-of cargohandling and transportation of rolling vehicles

Multi-purpose dry cargo ship with additionalpurpose of loading/unloading roll-on and roll-offcargo in dedicated RO/RO space

For a full definition of all class additional notations, see Pt.1 Ch.2.

3 Definitions

3.1 TermsThe definitions defined in Table 3 are used in this document.

Table 3 Definitions

Terms Definition

Long centre cargo hold Cargo hold having a length not less than 50% of the total length of thecargo hold region.

Ships occasionally carrying dry cargo in bulk Ships with minimum one seagoing loading condition with dry cargo inbulk specified in the loading manual.

Ships primarily intended for the carriage ofsolid bulk cargoes

Ships specified as a bulk carrier and where many of seagoing loadedconditions in the loading manual are having dry cargoes in bulk.

4 Documentation

4.1 Documentation requirements4.1.1 General dry cargo ship, Multi-purpose dry cargo ship, Bulk carrier and Ore carrierDocumentation shall be submitted as required in Table 4.

Table 4 Documentation requirements - General dry cargo ship, Multi-purpose dry cargo ship, Bulkcarrier and Ore carrier

Object Documentation type Additional description Info

I020– control system functionaldescription AP

I030 – system block diagram(topology) AP

I050– power supplyarrangement AP

Z030– arrangement plan detectors and alarm panel AP

Water ingressalarm system 1)

Z262 – report from test atmanufacturer

type test report AP, TA

Cargo securingarrangements 2)

Z030 – arrangement plan including position of fixed cargo securing devices,including MSL FI



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Cargo securingdevices, fixed 2)

H050 – structural drawing supporting structure for fixed cargo securing devices AP

Internal access 3) H200 – ship structure accessmanual

the plan shall include details enabling verification ofcompliance with requirements to safe access to andwithin, and forward of, the cargo area as required bySOLAS II-1/3-6

AP

Loading andunloading systems4)

Z030 – arrangement planFI

1) Required for ships with the ship type notation Bulk carrier or Ore carrier. Only required for ships with the shiptype notation General dry cargo ship or Multi-purpose dry cargo ship, if intended for occasional carriage of drycargoes in bulk.

2) Only required if fixed cargo securing devices are installed.3) Only required if the class notation ESP is assigned for ships of gross tonnage 20 000 dwt and above with the ship

type notation Bulk carrier or Ore carrier.4) Only required if a loading and unloading system other than grabs is installed.

AP = for approval, FI = for information, TA = covered by type approval.

4.1.2 X carrierDocumentation shall be submitted as required by Table 5.

Table 5 Documentation requirements - X carrier


H112 – loading sequencedescription, preliminary AP, VS

Ship hull structureH114 – loading sequencedescription, final AP, VS

Loading andunloading systems Z030 – arrangement plan FI

AP = for approval, FI = for information, VS = vessel specific.

4.1.3 Great lakes bulk carrierAll documentation requirements are covered by main class.

4.1.4 For general requirements for documentation, including definition of the info codes, see DNV-CG-0550Sec.6.For a full definition of the documentation types, see DNV-CG-0550 Sec.5.

5 Compliance documentation

5.1 Required compliance documentation5.1.1 General dry cargo ship, Multi-purpose dry cargo ship, Bulk carrier and Ore carrierProducts shall have compliance documents as required by Table 6.



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Table 6 Compliance documents - General dry cargo ship, Multi-purpose dry cargo ship, Bulkcarrier and Ore carrier

Object Compliancedocument type Issued by Compliance standard 1) Additional description

Water ingress alarm system 2) PC Society

Cargo securing devices, fixed 3) PD Manufacturer 4)

1) Unless otherwise specified the compliance standard is the Society's rules.2) Required for ships with the ship type notation Bulk carrier or Ore carrier. Only required for ships with the ship

type notation General dry cargo ship or Multi-purpose dry cargo ship, if intended for occasional carriage of drycargoes in bulk.

3) Only required if fixed cargo securing devices are installed.4) Upon request, product certificate issued by the Society in accordance with DNV-CP-0068 may be provided.

PC = product certificate, PD = product declaration

5.1.2 For general compliance documentation requirements, see DNV-CG-0550 Sec.4.For a definition of the compliance document types, DNV-CG-0550 Sec.3.

6 Testing

6.1 Testing during newbuilding6.1.1 Water ingress alarmsRequirements for testing water ingress alarms are given in Sec.2 [8.1.4] and Sec.2 [8.2.4].

6.1.2 De-watering system for drainage of forward spacesRequirements for testing de-watering system for drainage of forward spaces are given in Sec.2 [8.3.3].



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SECTION 2 COMMON REQUIREMENTSSymbols

For symbols not defined in this section, see Pt.3 Ch.1 Sec.4 [2].

aX, aY, aZ = longitudinal, transverse and vertical accelerations, in m/s2, at xG, yG, zG, as defined in Pt.3Ch.4 Sec.3 [3.2]

BH = for holds with vertical inner side connected to inner bottom:BH = BIB, as shown in Figure 3for holds with slanted longitudinal bulkhead connected to inner bottom:BH = breadth of the cargo hold, in m, measured at mid-length of the cargo hold and at theintersection of longitudinal bulkhead and main deck, as shown in Figure 4for holds with hopper tank and top wing tank:BH = breadth of the cargo hold, in m, measured at mid-length of the cargo hold and at themid height between the top of hopper tank and the bottom of topside tank, see Figure 5

BIB = breadth of inner bottom, in m, measured at mid-length of the cargo hold, see Figure 3 toFigure 5

fdc = dry cargo factor:

fdc = 1.0 for strength assessmentfdc = 0.5 for fatigue assessment

hC = height of bulk cargo, in m, from the inner bottom to the upper surface of bulk cargo, asdefined in [3.3.1] or [3.3.2]

hDB = height, in m, of the double bottom at the centreline, measured at mid-length of the cargohold, see Figure 3 to Figure 5

hHPL = for holds with vertical inner side connected to inner bottom:

hHPL = 0for holds with slanted longitudinal bulkhead connected to inner bottom:

hHPL = hHPUfor holds with hopper tank:

hHPL = vertical distance, in m, from the inner bottom at centreline to the upper intersectionof hopper tank and side shell or inner side for double side ships, determined at mid length ofthe considered cargo hold, as shown in Figure 5

hHPU = for cargo holds with no top wing tank:

hHPU = vertical distance, in m, from the inner bottom at centreline to the intersection oflongitudinal bulkhead and main deck, determined at mid length of the cargo hold at midship,as shown in Figure 3 and Figure 4for cargo holds with top wing tank:

hHPU = vertical distance, in m, from the inner bottom at centreline to the lower intersectionof topside tank and side shell or inner side for double side ships, determined at mid length ofthe cargo hold at midship, as shown in Figure 5

KC = coefficient:

for inner bottom, hopper tank, transverse andlongitudinal bulkheads, lower stool, vertical upper stool,inner side and side shell

for topside tank, main deck and sloped upper stool



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lH = length of the cargo hold, in m, at the centreline between the transverse bulkheads, see Figure3 to Figure 5. This shall be measured to the mid-depth of the corrugated bulkhead(s) if fitted

lSF = side frame span, in m, as defined in Figure 1, shall not be less than 0.25 D

M = mass, in t, of the bulk cargo being consideredMFull = cargo mass, in t, in a cargo hold corresponding to the volume up to the top of the hatch

coaming with a density of the greater of MH/VFull or 1.0 t/m3

MFull = 1.0 VFull but not less than MHMH = cargo mass, in t, in a cargo hold that corresponds to the homogeneously loaded condition at

maximum draught with consumables which is typically 50%MHD = maximum allowable cargo mass, in t, in a cargo hold according to design loading conditions

with specified holds empty at maximum draught with consumables which is typically 50%Pbs = static internal pressure due to dry bulk cargo, in kN/m2, as defined in [3.4.2]Pbd = dynamic inertial pressure due to dry bulk cargo, in kN/m2, as defined in [3.4.3]VFull = volume, in m3, of cargo hold up to top of the hatch coaming:

VFull = VH + VHCVH = volume, in m3, of cargo hold up to level of the intersection of the main deck with the hatch

coaming excluding the volume enclosed by hatch coaming, see Figure 3 to Figure 5VHC = volume, in m3, of the hatch coaming, from the level of the intersection of the main deck with

the hatch side coaming to the top of the hatch coaming, determined for the cargo hold atmidship, as shown in Figure 3 to Figure 5

VTS = total volume, in m3, of the portion of the lower bulkhead stools within the cargo hold length lHand inboard of the hopper tanks

x, y, z = x, y and z coordinates, in m, of the load point with respect to the reference coordinatesystem defined in Pt.3 Ch.4 Sec.1 [1.2.1]

xG, yG, zG = x, y and z coordinates, in m, of the volumetric centre of gravity of the fully filled cargo hold,i.e. VFull, considered with respect to the reference coordinate system defined in Pt.3 Ch.4Sec.1 [1.2]

In case of partially filled cargo hold, xG, yG, zG shall be:xG, yG = volumetric centre of gravity of the cargo holdzG = hDB + hC‐cl / 2

zC = height of the upper surface of the cargo above the baseline in way of the load point, in m:

zC = hDB + hCα = angle, in deg, between panel considered and the horizontal planeψ = assumed angle of repose, in deg, of bulk cargo; shall be:

ψ = 30° in generalψ = 35° for iron ore (with ρc = 3.0 t/m3) and for bulk cargoes with ρc ≥ 1.78 t/m3

ψ = 25° for cementρc = density of bulk cargo, in t/m3, as defined in [3.3.3]



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1 Introduction

1.1 IntroductionThese rules includes common requirements for dry cargo ships in addition to those that are applicable for theassignment of main character of class.

1.2 ScopeThis section describes common requirements for dry cargo ships in addition to the requirements described inPt.3, including:

— structural design principles, see [2]— pressure and forces due to dry bulk cargo, see [3]— design load scenarios, see [4]— hull local scantling, see [5]— additional safety measures for ships intended to carry dry cargo in bulk, see [6]— additional safety measures for ships with the class notation ESP, see [7]— water ingress alarms and drainage of forward spaces, see [8].

1.3 Application

1.3.1 Unless otherwise specified in the following subsections, the requirements given in this section shall beapplied to dry cargo ships described in Sec.5 to Sec.9.For ships with the ship type notation Bulk carrier (with CSR) only the requirements given in [8.2] and [8.3]are applicable.

1.3.2 For dry cargo ships, inclusive those with CSR, intended to carry cargo with temperatures above80°C and/or below 0°C, Pt.3 Ch.1 Sec.2 [3.7.2], Pt.3 Ch.3 Sec.1 [2.1.5] and Pt.3 Ch.3 Sec.1 [2.4.2] areapplicable.

1.3.3 For dry cargo ships, inclusive those with CSR, intended to operate in areas with low air temperatures,i.e. design temperatures below -10°C, the class notation DAT-B is mandatory, see Pt.6 Ch.6 Sec.6.

2 Structural design principles

2.1 Structural arrangement - double side structure2.1.1 Double sideA ship has a double side configuration, if each ship side for all cargo holds is constructed by the side shell anda longitudinal bulkhead connecting the double bottom and the strength deck. Hopper side tanks and top wingtanks may, where fitted, be integral parts of the double side configuration.

2.1.2 Primary supporting membersDouble side web frames shall be fitted in line with primary supporting members in double bottom or inhopper tanks, where fitted, or aligned with large brackets. Where top side tanks are fitted, double side webframes shall be aligned with web frames or large brackets.Transverse primary supporting members shall be fitted in way of hatch end beams or similar large deckopening supporting transverse structure.



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Horizontal side stringers or scarfing brackets shall be fitted aft of the collision bulkhead in line with fore peakstringers, and forward of engine room bulkhead in line with platform decks in machinery spaces.

2.1.3 Plating connectionsInner hull plating and hopper tank structures, where fitted, shall be supported at forward and aft ends, e.g.by scarfing brackets in way of the collision bulkhead and the engine room bulkhead.Connection between the inner hull plating and the inner bottom plating shall be designed such that stressconcentration is minimised. Connections of hopper tank plating with inner hull and with inner bottom shall besupported by a longitudinal girder. When a hopper tank is not fitted, the inner hull plating shall be supportedby a longitudinal girder below the inner bottom plating and the inner bottom plating shall be supported byscarfing brackets.

2.2 Structural arrangement - single side structure2.2.1 Single sideA ship has a single side configuration, if other than the double side configuration as given in [2.1.1].

2.2.2 Tripping bracketsCargo hold side frames made of angles or bulb profiles having a span lSF > 5 m shall be supported by trippingbrackets at the middle of the span.

2.2.3 Side frames in way of hatch end beams in ships without top wing tankIn ships without top wing tank, frames at hatch end beams shall be reinforced to withstand the additionalbending moment from the deck structure.

2.2.4 Upper and lower bracketThe length of the lower bracket, lb in Figure 1, shall not be less than 0.12 lSF.The length of the upper bracket, lb in Figure 1, shall not be less than 0.07 lSF.When the length of the free edge of the bracket is more than 40 times the net plate thickness, a flange shallbe fitted. The flange width shall be at least 1/15 of the length of the free edge.



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Figure 1 Dimensions of side frames - single side skin dry cargo ship

2.3 Structural arrangement - deck structure2.3.1 Web frame spacing in topside tanksThe spacing of web frames in topside tanks shall not be greater than 6 frame spaces. Other arrangementswill be considered on a case-by-case basis.

2.3.2 Cross deck between hatchesTransverse members supporting the cross deck shall be supported by side or top side tank transversemembers.Assessment of the primary supporting members shall be performed applying an advanced calculation methodin compliance with the requirements in Pt.3 Ch.6 Sec.6 [2.2].Smooth connection of the strength deck at side with the cross deck shall be ensured by a plate ofintermediate thickness.



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2.3.3 Topside tank structuresTopside tank structures, where fitted, shall be supported at forward and aft ends, e.g. by scarfing brackets inway of the collision bulkhead and the engine room bulkhead.

2.3.4 Large openings and hatchwaysFor hatchways located within the cargo area, radiused insert plates with thickness not less than determinedaccording to the formula given below, shall be fitted in way of corners.

The radius of circular corners shall not be less than 5% of the hatch width, where a continuous longitudinaldeck girder is fitted below the hatch coaming.

Corner radius, in the case of the arrangement of two or more hatchways athwartships, is considered by theSociety on a case-by-case basis.

For hatchways located within the cargo area, insert plates are not required in way of corners where theplating cut-out has an elliptical or parabolic profile and the half axes of elliptical openings, or the half lengthsof the parabolic arch, are not less than:

— 1/20 of the hatchway width or 600 mm, whichever is the lesser, in the transverse direction— twice the transverse dimension, in the fore and aft direction.

Where insert plates are required, their net thickness shall be obtained, in mm, from the following formula:

without being taken less than toff or greater than 1.6 toff

where:

toff = offered net thickness, in mm, of the deck at the side of the hatchwaysb = width, in m, of the hatchway considered, measured in the transverse directionℓ = length, in m, in way of the corner considered, of the cross deck strip between two consecutive

hatchways, measured in the longitudinal direction.

For the extreme corners of end hatchways, insert plates are required.

Where insert plates are required, the arrangement is shown in Figure 2 which d1, d2, d3 and d4 shall begreater than the stiffener spacing.

For hatchways located outside the cargo area, a reduction in the thickness of the insert plates in way ofcorners may be considered by the Society on a case-by-case basis.

For ships having length, L, of 150 m or above, the corner radius, the thickness and the extent of insert platemay be determined by the results of a direct strength assessment according to Pt.3 Ch.7, including bucklingcheck and fatigue strength assessment of hatch corners according to Pt.3 Ch.8 and Pt.3 Ch.9 respectively.



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Figure 2 Hatch corner insert plate

2.4 Structural arrangement - plane bulkheadsFloors shall be fitted in the double bottom in line with the plane transverse bulkhead.

2.5 Detailed design2.5.1 StiffenersFor ships intended for the carriage of dry cargoes in bulk the requirements given in Pt.3 Ch.3 Sec.6 [3.4.1]shall be complied with, applying the additional design load sets given in [5.1.3].

3 Pressures and forces due to dry bulk cargo

3.1 ApplicationThe pressures and forces due to dry cargo in bulk in a cargo hold shall be determined both for fully andpartially filled cargo holds according to [3.4] and [3.5].

3.2 Hold definitions3.2.1 Geometrical characteristicsThe main geometrical elements of a box shaped cargo hold are shown in Figure 3.



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Figure 3 Box shaped cargo hold - definition of cargo hold parameters

The main geometrical elements of a cargo hold of an ore carrier with slanted longitudinal bulkhead are shownin Figure 4.

Figure 4 Ore carrier with slanted longitudinal bulkhead - definition of cargo hold parameters

The main geometrical elements of a cargo hold with hopper tank and top wing tank are shown in Figure 5.



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Figure 5 Cargo hold with hopper tank and top wing tank - definition of cargo hold parameters

3.2.2 Fully and partially filled cargo holdsThe definitions of a fully and partially filled dry bulk cargo holds are as follows:

a) Fully filled hold: the dry bulk cargo density is such that the cargo hold is filled up to the top of the hatchcoaming, as shown in:

— box shaped cargo hold: Figure 6— ore carrier with slanted longitudinal bulkhead: Figure 7— cargo hold with hopper tank and top wing tank: Figure 8.

The upper surface of the cargo and its effective height in the hold hC shall be determined in accordancewith [3.3.1].

b) Partially filled hold: the cargo density is such that the cargo hold is not filled up to the top of the hatchcoaming, as shown in:

— box shaped cargo hold: Figure 9— ore carrier with slanted longitudinal bulkhead: Figure 10— cargo hold with hopper tank and top wing tank: Figure 11 or Figure 12.

The upper surface of the cargo and its effective height in the hold hC shall be determined in accordancewith [3.3.2].

3.3 Dry cargo characteristics3.3.1 Definition of the upper surface of dry bulk cargo for full cargo holdsFor a fully filled cargo hold as defined in [3.2.2], including non-prismatic holds, the effective upper surface ofthe cargo is an equivalent horizontal surface at hC, in m, above inner bottom at centreline as shown in Figure6 to Figure 8.

The value of hC shall be calculated at mid length of the cargo hold at the midship, shall be kept constant overthe cargo hold region area, and is determined as follows:

where:



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S0 = shaded area, in m2, shall be:Figure 6: S0 = 0Figure 7: S0 = shaded area above the intersection of longitudinal bulkhead and main deck and up tothe level of the intersection of the main deck with the hatch coaming, determined for the cargo holdat the midshipFigure 8: S0 = shaded area above the lower intersection of top side tank and side shell or innerside, as the case may be, and up to the level of the intersection of the main deck with the hatchcoaming, determined for the cargo hold at the midship.

Figure 6 Box shaped cargo hold - definition of effective upper surface of cargo for a full cargo hold



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Figure 7 Ore carrier with slanted longitudinal bulkhead - definition of effective upper surface ofcargo for a full cargo hold

Figure 8 Cargo hold with hopper tank and top wing tank - definition of effective upper surface ofcargo for a full cargo hold

3.3.2 Definition of the upper surface of dry bulk cargo for partially filled cargo holdsFor any partially filled cargo hold, as defined in [3.2.2], including non-prismatic holds, the effective uppersurface of the cargo shall be made of three parts:

— one central horizontal surface of breadth BH/2, in m, at a height hC‐CL, in m, above the inner bottom— a sloped surface at each side with an angle ψ/2, in degrees, between the central horizontal surface, andthe side shell or inner hull, as shown in Figure 9 to Figure 11, or the hopper plating, as shown in Figure12, as the case may be.

The height of cargo surface hC, in m, shall be calculated at mid length of the considered cargo hold and shallbe constant over the length of the hold as follows:



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For :

For :

For :

where:

h1 = height, in m, shall be:

— for h1 ≥ 0 as shown in Figure 9 and Figure 11:

— for h1 < 0 as shown in Figure 10 and Figure 12

hC‐CL = height, in m, of the cargo surface at the centreline, as shown in Figure 9 to Figure 12B2 = maximum breadth of the cargo, in m, as shown in Figure 10 and Figure 12.



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Figure 9 Box shaped cargo hold- definition of the effective upper surface of cargo for a partiallyfilled cargo hold

Figure 10 Ore carrier with slanted longitudinal bulkhead - definition of the effective upper surfaceof cargo for a partially filled cargo hold



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Figure 11 Cargo hold with hopper tank and top wing tank - definition of the effective uppersurface of cargo for a partially filled cargo hold when h1 ≥ 0

Figure 12 Cargo hold with hopper tank and top wing tank - definition of the effective uppersurface of cargo for a partially filled cargo hold when h1 < 0

3.3.3 Mass and densityThe dry cargo mass and the density of the cargo shall be as follows:

— for strength assessment: the values defined in Table 1— for fatigue assessment: the values defined in Table 2.



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Table 1 Dry bulk cargo mass and density for strength assessment

Homogeneous loading condition Alternate loading condition 1)

Ship typeCargo massCargo density fully filled hold partially filled

hold 2) 3) fully filled hold partiallyfilled hold 3)

M M = MH M = MH M = MHD M = MHD

In generalρC

but not less than 0.7 4)

maximum valuespecified in theloading manual

maximum valuespecified in theloading manual

M M = MH M = MH M = MH M = MHOre

carrier ρC ρC = 3.0 ρC = 3.0

1) Alternate loading conditions are only applicable if such conditions are included in the loading manual.2) Homogeneous loading condition with partially filled hold is only applicable if loading conditions having a mass

density not less than 1.0 are included in the loading manual.3) Loading conditions with partially filled hold are only applicable if filling level heights less than 90% is included in the

loading manual.4) If a mass density of 0.7 for all cargo holds represents a total cargo intake Σ 0.7 MFull that are exceeding the total

cargo capacity of the vessel ρC may be reduced after special consideration.

Table 2 Dry bulk cargo mass and density for fatigue assessment

Homogenous loading condition Alternate loading condition 1)Ship type Cargo mass

Cargo density fully filled hold partially filled hold partially filled hold

M M = MH M = MHD

In generalρC

N/A maximum value specifiedin the loading manual

M M = MHOrecarrier ρC

N/AρC = 3.0

N/A

1) Alternate loading conditions are only applicable if such conditions are included in the loading manual.

3.3.4 FE applicationThe following process shall be applied for the bulk cargo pressure loads used in FE analysis:

a) determine hc according to [3.3.1] for fully filled cargo hold or [3.3.2] for partially filled cargo holdb) determine the corresponding static pressure as defined in [3.4.2] and static shear pressure as defined in

[3.5.2] using ρc and apply them in the FE modelc) calculate the actual mass of cargo, Mactual, in t



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d) determine the effective cargo density, in t/m3:

where:

M = cargo mass being used when determining hc in a)Mactual = calculated actual cargo mass when applying static pressures and static shear loads in b)

e) calculate the final pressure distribution and shear load using ρeff instead of ρc.

3.4 Dry bulk cargo pressures3.4.1 Total pressureThe total pressure due to dry bulk cargo acting on any load point of a cargo hold boundary, in kN/m2, shallbe:

for strength assessment of intact conditions for static (S) design load scenarios, given in[4]

for strength assessment of intact conditions and fatigue assessment for static plusdynamic (S+D) design load scenarios, given in [4].

Static and dynamic pressures as defined in [3.4.2] and [3.4.3] for FE analysis shall be determined using ρeffinstead of ρc.

3.4.2 Static pressureThe dry bulk cargo static pressure Pbs, in kN/m

2, shall be:

but not less than 0.

3.4.3 Dynamic pressureThe dry bulk cargo dynamic pressure Pbd, in kN/m

2, for each load case shall be:

for z ≤zc

for z > zc

3.5 Shear load3.5.1 ApplicationFor FE strength assessment and FE fatigue assessment, the following shear load pressures shall be applied inaddition to the dry bulk cargo pressures defined in [3.4] when the load point elevation, z, is lower or equal tozc:

— for static (S) design load scenarios, given in [4], static shear load, Pbs-s, due to gravitational forces actingon hopper tanks and lower stools plating, as defined in [3.5.2]



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— for static plus dynamic (S+D) design load scenarios, given in [4], the following dynamic shear loadpressures:Pbs-s + Pbs-d for the hopper tank and the lower stool plating, as defined in [3.5.3]Pbs-dx for the inner bottom plating in the longitudinal direction, as defined in [3.5.4]Pbs-dy for the inner bottom plating in the transverse direction, as defined in [3.5.4].

Shear loads as defined in [3.5.2] to [3.5.4] for FE analysis shall be determined using ρeff instead of ρc.

3.5.2 Static shear load on the hopper tank and lower stool platingThe static shear load pressure, Pbs-s (positive downward to the plating) due to dry bulk cargo gravitationalforces acting on hopper tank and lower stool plating, in kN/m2, shall be:

3.5.3 Dynamic shear load on the hopper tank and lower stool platingThe dynamic shear load pressure, Pbs-d (positive downward to the plating) due to dry bulk cargo forces onthe hopper tank and lower stool plating, in kN/m2, for each dynamic load case shall be:

3.5.4 Dynamic shear load along the inner bottom platingThe dynamic shear load pressures, Pbs-dx in the longitudinal direction (positive to bow) due to dry bulk cargoforces acting along the inner bottom plating, in kN/m2, shall be, for each dynamic load case, as:

The dynamic shear load pressures, Pbs-dy in the transverse direction (positive to port) due to dry bulk cargoforces acting along the inner bottom plating, in kN/m2, shall be, for each dynamic load case, as:

4 Design load scenarios

4.1 GeneralThe design load scenarios given in Pt.3 Ch.4 Sec.7 shall be complied with, in addition to the additionalprincipal design load scenarios for dry cargo ships given in [4.2].



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4.2 Additional principal design load scenarios for dry cargo ships4.2.1 Additional principal design load scenarios for strength assessmentThe additional principal design load scenarios for strength assessment of dry cargo ships are given in Table 3.

Table 3 Additional principal design load scenarios for strength assessment

Design load scenario

6 1) 7 2)

FEM assessment ofloading/unloading

in harbour

enhanced floodedrequirements

static (S) accidental (A)

VBM Msw-p Msw-f + 0.8 Mwv

HBM - -

VSF Qsw-p Qsw-f + 0.8 Qwv

hull girderloads 5)

TM - -

exposed decks - -

external shell PS -

superstructure sides - -Pex

superstructure end bulkheads and deckhouse walls - -

boundaries of water ballast tanks 3) -

boundaries of tanks other than water ballast tanksPls-3

-

watertight bulkheads - -

boundaries of bulk cargo holds Pbs Pbf-s4)

Pin

internal structures in tanks - -

Pdlexposed decks and non-

exposed decks and platforms Pdl-s -

FU heavy units on internal and external decks FU-s -

load component

localloads 6)

P weather deck hatch covers PC -



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Design load scenario

6 1) 7 2)

FEM assessment ofloading/unloading

in harbour

enhanced floodedrequirements

static (S) accidental (A)

1) Application is further given in [4.2.2].2) Application is further given in [4.2.3].3) WB cargo hold is considered as ballast tank.4) Static pressure Pbf-s shall be applied to vertically corrugated transverse bulkheads only.5) Hull girder loads:

Msw‐f = permissible vertical still water bending moment in flooded condition as defined in Sec.4 [2.1.1]

Msw‐p = permissible vertical still water bending moment for harbour/sheltered water operation as defined inPt.3 Ch.4 Sec.4 [2.2.3]

Qsw‐f = permissible vertical still water shear force in flooded condition as defined in Sec.4 [2.1.1]

Qsw‐h = permissible vertical still water shear force for harbour/sheltered water operation as defined in Pt.3Ch.4 Sec.4 [2.4.3].

6) Local loads:PS = hydrostatic sea pressure as given in Pt.3 Ch.4 Sec.5 [1.2]

Pls‐3 = static tank pressure during normal operations at harbour/sheltered water as given in Pt.3 Ch.4 Sec.6[1.2.3]

Pbs = static dry bulk cargo pressure as given in [3.4.2]

Pbf‐s = static pressure on vertically corrugated transverse bulkhead of a flooded cargo hold as given in Sec.4[2.2.6]

Pdl‐s = static pressure due to distributed load on exposed decks as given in Pt.3 Ch.4 Sec.5 [2.3.1], andstatic pressure due to distributed load in on non-exposed decks and platforms as given in Pt.3 Ch.4Sec.6 [2.2.1]

FU‐s = concentrated static force due to unit load on exposed decks as given in Pt.3 Ch.4 Sec.5 [2.3.2], andconcentrated static force due to unit load on non-exposed decks as given in Pt.3 Ch.4 Sec.6 [2.3.1]

PC = uniform cargo load on hatch covers due to cargo loads as given in Pt.3 Ch.12 Sec.4 [2.3.1].

4.2.2 FEM assessment of loading/unloading in harbourDesign load scenario 6, FEM assessment of loading/unloading in harbour, defined in Table 3 applies to drycargo ships with minimum one of the following:

— ships with harbour/sheltered water loaded loading conditions included in the loading manual— ships where guidance for loading/unloading sequences are required.

Guidance note:The application of design load scenario 6 is further defined in tables for standard FE design load combinations given in:

— General dry cargo ship or Multi-purpose dry cargo ship, with a long centre cargo hold: Sec.5 Table 1.

— General dry cargo ship, Multi-purpose dry cargo ship or Bulk carrier (without CSR) assigned the additional notation HC:Pt.6 Ch.1 Sec.4 Table 11 to Pt.6 Ch.1 Sec.4 Table 17.

— Ore carrier assigned the additional notation OC: Pt.6 Ch.1 Sec.5 Table 6 to Pt.6 Ch.1 Sec.5 Table 11.




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Guidance note:The harbour FE design load combinations, applying permissible limits for harbour/sheltered water operation, may be decisive forthe structural strength. For ships where the harbour FE design load combinations are governing, the permissible limits for harbour/sheltered water operation should be established by enveloping the most severe loaded conditions given in the loading manual and/or loading/unloading sequences.


4.2.3 Enhanced flooded requirementsDesign load scenario 7, Enhanced flooded requirements, defined in Table 3 applies to ships assigned shiptype notation Ore carrier or Bulk carrier (without CSR), complying with criteria further given in Sec.4[1.3].The application of design load scenario 7 is limited to the following:

— transverse vertically corrugated watertight bulkheads separating cargo holds in flooded condition: Sec.4[3]

— allowable hold loading in flooded conditions: Sec.4 [4]— vertical hull girder bending and shear strength in flooded conditions: Sec.4 [5].

5 Hull local scantling

5.1 Design load sets for ships intended to carry dry bulk cargo5.1.1 ApplicationThe design load sets given in [5.1.3] and [5.1.4] apply to the cargo hold region of dry cargo ships, inaddition to the design loads sets given in Pt.3 Ch.6 Sec.2, for the following structural members:

— additional design load sets for plating and stiffeners, in Table 5— additional design load sets for primary supporting members, in Table 6.

5.1.2 Load componentsThe static and dynamic load components shall be determined in accordance with the principal design loadscenarios given in [4].Radius of gyration, kr, and metacentric height, GM, shall be in accordance with Table 4.



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Table 4 kr and GM values

Loading condition 1) 3) Application TLC kr GM

in general 0.35Bhomogeneous loading, fully filled

Ore carrier 0.25B0.12B

in general 0.42Bhomogeneous heavy cargo, partiallyfilled Ore carrier 0.25B

0.25B

in general 0.35Balternate light cargo, fully filled

Ore carrier 0.20B0.12B

in general 0.40B

full loadcondition

alternate heavy cargo, partially filledOre carrier 0.20B

0.20B

steel coil loading 2)all ships designatedfor the carriageof steel products

TSC

0.42B 0.25B

in general 0.40B 0.25Bheavy ballast condition

Ore carrierTBAL-H

0.35B 0.30B

in general 0.45Bnormal ballast condition

Ore carrierTBAL

0.35B0.33B

1) For multi-port (MP) loading conditions with draught greater than or equal to 0.9TSC, the values of kr and GM, unlessprovided in the loading manual, shall be as those from the most appropriate full load condition.For multi-port (MP) loading conditions with draught between TBAL-H and 0.9TSC, the values of kr and GM, unlessprovided in the loading manual, shall be obtained by linear interpolation, based on the draught, between the heavyballast condition and the most appropriate full load condition.

For multi-port (MP) loading conditions with a draught below TBAL-H, the values of kr and GM for the heavy ballastcondition shall be used.

2) When steel coil loading condition is provided by the designer in the loading manual, this condition shall be assessedwith draught, kr and GM values given in this table.

3) Block loading conditions shall be assessed with draught, kr and GM values given in this table for homogeneousheavy cargo loading condition.



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5.1.3 Additional design load sets for plating and stiffeners of dry cargo shipsAdditional design load sets for plating and stiffeners of dry cargo ships are given in Table 5.

Table 5 Additional design load sets for plating and stiffeners of dry cargo ships

Structuralmember

Designloadset

Designload

scenario

Loadcomponent 1) Draught Acceptancecriteria Loading condition

BC-1 2 Pbs + Pbd TSC AC-II

BC-2 1 Pbs - AC-Ihomogeneous loading, fully filled


BC-4 1 Pbs - AC-Ihomogeneous heavy cargo, partially filled


BC-6 1 Pbs - AC-Ialternate light cargo, fully filled


Boundariesof bulk

cargo hold

BC-8 1 Pbs - AC-Ialternate heavy cargo, partially filled

1) Local loads:


Pbd = dynamic dry bulk cargo pressure as given in [3.4.3].



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5.1.4 Additional design load sets for primary supporting members of dry cargo shipsAdditional design load sets for primary supporting members of dry cargo ships are given in Table 6.The severest loading conditions from the loading manual or otherwise specified by the designer shall beconsidered for the calculation of Pbs + Pbd and Pbs in design load sets BC-11 to BC-14. If loading/unloadingsequences are provided the additional design load sets BC-15 and BC-16 applies.

Table 6 Additional design load sets for primary supporting members of dry cargo ships

Structuralmember

Designloadset

Designload

scenario

Loadcomponent 6) Draught Acceptance

criteria Loading condition

WB-5 2Pls-1+Pld –(PS+PW)

1) TBAL-H2) AC-IIBoundaries of

ballast holdWB-6 1 Pls-3 - PS

1) TBAL-H2) AC-I

heavy ballast condition

BC-11 2Pbs + Pbd -(PS+PW)

1) TSC AC-II

BC-12 1 Pbs- PS1) TSC AC-I

full load condition

BC-13 2 (PS+PW) 1) TBAL-H/TBAL

3) AC-II

BC-14 1 PS1) TBAL-H/TBAL

3) AC-Iheavy/normal ballast condition

BC-15 6 Pbs- PS1) TMin

4) AC-I

Boundariesof bulk

cargo hold

BC-16 6 PS1) TMax

5) AC-Iloading/unloading in harbour

1) (PS+PW) and PS shall be considered for external shell only.2) Minimum draught among heavy ballast conditions shall be used.3) Maximum draught among all ballast conditions shall be used.4) Minimum draught with hold full according to loading/unloading sequences shall be used.5) Maximum draught with hold empty according to loading/unloading sequences shall be used.6) Local loads:

PS = hydrostatic sea pressure as given in Pt.3 Ch.4 Sec.5 [1.2]

PW = wave pressure as given in Pt.3 Ch.4 Sec.5 [1.3]

Pls‐1 = static tank pressure during normal operations at sea as given in Pt.3 Ch.4 Sec.6 [1.2.1]

Pls‐3 = static tank pressure during normal operations at harbour/sheltered water as given in Pt.3 Ch.4 Sec.6[1.2.3]

Pld = dynamic tank pressure as given in Pt.3 Ch.4 Sec.6 [1.3]


Pbd = dynamic dry bulk cargo pressure as given in [3.4.3].



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5.2 Cargo hold side frames of single side skin construction5.2.1 ApplicationRequirements in this subsection shall be applied to single side structure within the cargo hold region of drycargo ships with transverse framing.

5.2.2 Net section modulus and net shear sectional areaThe net section modulus Z, in cm3, and the net shear sectional area Ashr, in cm

2, in the mid-span area of sideframes subjected to lateral pressure shall not be less than:

where:

αm = coefficient:

αm = 0.42 for side frames of holds that may be empty in alternate conditionsαm = 0.36 for other ships

fbdg = bending coefficient 10

Cs = permissible bending stress coefficient for the design load set being considered:Cs = 0.75 for acceptance criteria set AC-ICs = 0.90 for acceptance criteria set AC-II

αS = coefficient:

αS = 1.1 for side frames of holds that may be empty in alternate conditionsαS = 1.0 for other side frames

ℓB = lower bracket length, in m, as defined in Figure 1 without integral bracket and in Figure 13 withintegral bracket

P = design pressures, in kN/m², for design load sets BC-1 to BC-8 as defined in Table 5 and SEA-1 toSEA-2 as defined in Pt.3 Ch.6 Sec.2 Table 1

Ct = permissible shear stress coefficient for the design load set being considered:Ct = 0.75 for acceptance criteria set AC-ICt = 0.90 for acceptance criteria set AC-II.



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Figure 13 Side frame integral lower bracket length

5.2.3 Lower bracket of side frameAt the level of the lower bracket, as shown in Figure 1 for side frames without integral bracket or in Figure 13for side frames with integral bracket, the net section modulus of the frame and bracket, or integral bracket,with associated shell plating, shall not be less than twice the required net section modulus Z, in cm3, for theframe mid-span area obtained from [5.2.2].

5.2.4 Upper bracket of side frameAt the level of the upper bracket, as shown in Figure 1 for side frames without integral bracket or in Figure 13for side frames with integral bracket, the net section modulus of the frame and bracket, or integral bracket,with associated shell plating, shall not be less than 1.5 times the net section modulus Z required for theframe mid-span area obtained from [5.2.2].

5.2.5 Side frames in ballast holdsIn addition to [5.2.2], for side frames in cargo holds designed to carry ballast water in heavy ballastcondition, the net section modulus Z, in cm3, and the net web thickness, tw, in mm, all along the span shallbe in accordance with Pt.3 Ch.6 Sec.5. The span of the side frame, lf, in m, shall be as defined in Pt.3 Ch.3Sec.7 [1.1] with consideration of end brackets.

6 Additional safety measures for ships intended to carry dry cargoin bulk

6.1 ApplicationRequirements of this subsection shall be applied for ships intended to carry dry cargo in bulk with one of thefollowing ship type notations, unless otherwise specified:

— General dry cargo ship or Multi-purpose dry cargo ship occasionally carrying dry cargo in bulk— Bulk carrier— Ore carrier.



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6.2 Corrosion protection of double side spaces6.2.1 Ore carriersFor ships with the ship type notation Ore carrier with a freeboard length LLL of not less than 150 m, wingvoid spaces in the cargo area shall have an efficient corrosion prevention system, such as hard protectivecoatings or equivalent.

Guidance note:The flag administration may require that the wing void spaces shall be considered as double skin void spaces that shall comply withSOLAS II-1/3-2.


6.2.2 Ships other than ore carriersFor other ships with a freeboard length LLL of not less than 150 m, the double side spaces in the cargo areashall have an efficient corrosion prevention system in accordance with Pt.3 Ch.3 Sec.4 [1.1.1].(SOLAS II-1/3-2 and MSC.277(85))

6.3 Enhanced flooded requirementsThe requirements given in Sec.4 are applicable to ships with following class notations:

— Bulk Carrier (without CSR), with HC(A), HC(B) or HC(B*)— Bulk Carrier (without CSR), with HC(M), carrying solid bulk cargoes having a density not less than 1.0t/m3.

— Ore Carrier, with OC(H) or OC(M), if any part of longitudinal bulkhead in any cargo hold is locatedwithin B/5 or 11.5 m, whichever is less, inboard from the ship’s side at right angle to the centerline atthe assigned summer load line. Only cargo holds in way of the double side space which do not meet thecriteria given above shall be considered flooded.

(SOLAS XII/5)

6.4 Double side configuration6.4.1 Double side widthThe requirements given in the following paragraphs are applicable to ships of double side configuration withfreeboard length LLL of not less than 150 m.The breadth of the double side measured perpendicular to the side shell from the top of double bottom to thestrength deck at any location within the length of the cargo hold region shall not be less than 1000 mm.The minimum clearance between the inner surfaces of the stiffeners inside the double side shall not be lessthan:

— 600 mm when the inner and/or the outer sides are transversely stiffened.— 800 mm when the inner and the outer sides are longitudinally stiffened. Outside the parallel part of thecargo hold region, the clearance may be reduced but shall not be less than 600 mm.

The minimum clearance is defined as the shortest distance measured between assumed lines connecting theinner surfaces of the stiffeners on the inner and outer sides.(SOLAS XII/6.2.2 and MSC.277(85))

6.4.2 Double side arrangementFor ships with freeboard length LLL of not less than 150 m, primary stiffening structures of the double sideshall not be placed inside the cargo hold space.For all ships, the double side spaces, with the exception of top-side wing tanks, if fitted, shall not be used forthe carriage of cargo.



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(Based on SOLAS XII/6.2.1 & 6.3 and MSC.277(85))

6.5 Protection against loading/discharge equipmentFor ships with freeboard length LLL of not less than 150 m, carrying solid bulk cargoes having a density notless than 1.0 t/m3, the requirements as follows are applicable, excluding ships with inner bottom constructionadapted for self-unloading,

— The notation Grab is mandatory.— Wire rope grooving in way of cargo holds openings is to be prevented by fitting suitable protection suchas half-round bar on the hatch side girders (i.e. upper portion of top side tank plates)/hatch end beams incargo hold and upper portion of hatch coamings.Guidance note:The protection half-round bar on hatch side girders/hatch end beams may be waived for following cases.

— Sloped hatch coamings are arranged to protect hatch side girders/hatch end beams. In such cases, the horizontal distance ofthe hatch opening edge at the hatch coaming top to the hatch sider/girder/hatch end beam at upper deck level should not beless than 20% of the hatch coaming height.

— Hatch coamings are aligned with vertically straight longitudinal bulkheads/transverse bulkheads, i.e., there are no specifichatch side girders/hatch end girders.


(SOLAS XII/6.4.1, MSC.277(85) and IACS UI SC208)

6.6 Single failure of cargo hold structuresFor ships with freeboard length LLL of not less than 150 m, carrying solid bulk cargoes having a density notless than 1.0 t/m3, the buckling requirements for the following areas shall comply with Pt.3 Ch.8, applyingthe additional design load sets given in [5.1].

— hatchway coaming— inner bottom— sloped stiffened panel of topside tanks and hopper tanks (if any)— inner side (if any)— top stool and bottom stool of transverse bulkhead (if any)— stiffened transverse bulkhead (if any)— side shell (if directly bounding the cargo hold).The partial safety factor shall be set to 1.15 as given in DNV-CG-0128 Sec.3 with closed form method (CFM).Alternatively if PULS method is utilised, the allowable buckling utilization factor given in Pt.3 Ch.8 Sec.1 [3.4]shall be divided by 1.15.(SOLAS XII/6.4.3, MSC.277(85) and IACS UI SC209)

6.7 Information on compliance with requirementsThis requirement is applicable to ships with one of the following ship type notations:

— Bulk carrier— Ore Carrier.The sentence "SOLAS XII, regulations 4, 5, 6 and 7, as appropriate, are complied with." shall be specified onthe front page of the following booklet,

— the final loading manual, or— the final loading sequence booklet if required as given in Pt.6 Ch.1 Sec.4 [2.1] or Pt.6 Ch.1 Sec.5 [2.1].(SOLAS XII/8)



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7 Additional safety measures for ships with class notation ESP

7.1 ApplicationRequirements of this subsection shall be applied for ships with the class notation ESP and intended to carrydry cargo in bulk.

7.2 Access to and within spaces in, and forward of, the cargo areaFor ships of gross tonnage 20 000 dwt and above, access to and within spaces in, and forward of, the cargoarea shall comply with SOLAS II-1/3-6 and IACS UI SC191.

7.3 Free-fall lifeboatFree-fall lifeboat shall be arranged complying with SOLAS III/31.1.8.

7.4 ForecastleA forecastle shall be arranged complying with CSR Pt.2 Ch.1 Sec.1 [1].

7.5 Corrosion protection of cargo hold spacesCargo hold spaces shall have corrosion protection complying with CSR Pt.2 Ch.1 Sec.2 [2.3].

7.6 Single side structureSingle side structure, if any, shall comply with CSR Pt.2 Ch.1 Sec.2 [3.2] in lieu of [2.2] for structure designprincipals, and CSR Pt.2 Ch.1 Sec.3 [1] in lieu of [5.2] for strength requirements.

7.7 Cargo hatch covers and hatch coamingsHatch covers and coamings for cargo holds shall be designed complying with CSR Pt.2 Ch.1 Sec.5.

8 Water ingress alarms and drainage of forward spaces

8.1 Water ingress alarms in single hold dry cargo ships8.1.1 ApplicationRequirements of this subsection shall be applied to single hold dry cargo ships which comply with SOLAS.

8.1.2 Performance requirementsSingle hold cargo ships shall be fitted with water level detectors giving audible and visual alarms on thenavigation bridge when the water level above the inner bottom in the cargo hold reaches a height of not lessthan 0.3 m and another level when such level reaches not more than 15% of the mean depth of the cargohold.(SOLAS II-1/23-3)The water ingress detector equipment shall be type tested in accordance with MSC.188 (79) Performancestandards for water level detectors on bulk carriers and single hold cargo ships other than bulk carriers, andbe suitable for the cargoes intended.



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Guidance note:The appendix to the classification certificate will contain information as to which cargoes the systems are approved for.


8.1.3 InstallationInstallation shall be carried out in accordance with [8.2.3].

8.1.4 TestingTesting shall be carried out in accordance with [8.2.4].

8.2 Water ingress alarms in dry cargo ships carrying dry cargo in bulk8.2.1 ApplicationThis subsection applies to dry cargo ships with one of the following ship type notations:


8.2.2 Performance requirementsThe ship shall be fitted with water level detectors giving audible and visual alarms on the navigation bridge:

— In each cargo hold, one when the water level above the inner bottom in any hold reaches a height of 0.5m and another at a height not less than 15% of the depth of the cargo hold but not more than 2.0 m.

— In any ballast tank forward of the collision bulkhead, when the liquid in the tank reaches a level notexceeding 10% of the tank capacity.

— In any dry or void space other than a chain cable locker, any part of which extends forward of theforemost cargo hold, at a water level of 0.1 m above the deck. Such alarms are not mandatory inenclosed spaces the volume of which does not exceed 0.1% of the ship's maximum displacement volume.

(SOLAS XII/12 and MSC.277(85))The water ingress detection system shall be type tested in accordance with MSC.188 (79) Performancestandards for water level detectors on bulk carriers and single hold cargo ships other than bulk carriers, andbe suitable for the cargoes intended.

Guidance note:The appendix to the classification certificate will contain information as to which cargoes the systems are approved for.


8.2.3 InstallationThe sensors shall be located in a protected position that is in communication with the after part of the cargohold or tank and or space, such that the position of the sensor detects the level that is representative of thelevels in the actual hold space or tank.These sensors shall be located:

— either as close to the centre line as practicable, or— at both the port and starboard sides.

The detector installation shall not inhibit the use of any sounding pipe or other water level gauging device forcargo holds or other spaces.Detectors and equipment shall be installed where they are accessible for survey, maintenance and repair.Any filter element fitted to detectors shall be capable of being cleaned before loading.Electrical cables and any associated equipment installed in cargo holds shall be protected from damage bycargoes or mechanical handling equipment associated with cargo handling operations, such as in tubes ofrobust construction or in similar protected locations.



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The part of the electrical system which has circuitry in the cargo area shall be arranged intrinsically safe.The power supply shall be in accordance with Pt.4 Ch.9 Sec.3 [2.2].

8.2.4 TestingAfter installation the system is subject to testing consisting of:

— inspection of the installation— demonstration of facilities for filter cleaning— demonstration of facilities for testing of the detector— test of all alarm loops— test of the alarm panel functions.

8.3 Availability of pumping systems8.3.1 ApplicationThis subsection applies to dry cargo ships with one of the following ship type notations:


8.3.2 Availability of drainage for forward spacesThe means for draining and pumping ballast tanks forward of the collision bulkhead, and bilges of dryspaces, any part of which extends forward of the foremost cargo hold, shall be capable of being broughtinto operation from a readily accessible enclosed space. The location shall be accessible from the navigationbridge or propulsion machinery control position, without need for traversing exposed freeboard orsuperstructure decks.(SOLAS XII/13 and MSC.277(85))This does not apply to the enclosed spaces the volume of which does not exceed 0.1% of the ship'smaximum displacement volume. Nor does it apply to the chain cable lockers.

Guidance note:Where pipes serving such tanks or bilges pierce the collision bulkhead, as an alternative to the valve control specified in Pt.4 Ch.6Sec.3 [1.4.2], valve operation by means of remotely operated actuators may be accepted, provided that the location of such valvecontrols complies with this regulation.


The dewatering system for ballast tanks forward of the collision bulkhead and for bilges of dry spaces, anypart of which extends forward of the foremost cargo hold, shall be designed to remove water from theforward spaces at a rate of not less than 320A m3/h, where A is the cross-sectional area in m2 of the largestair pipe or ventilator pipe connected from the exposed deck to a closed forward space that is required to bedewatered by these arrangements.(IACS UR M65)

8.3.3 Testing and installationThe installation and testing on board shall be in accordance with Pt.4 Ch.6 Sec.4 for bilge systems.



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SECTION 3 STEEL COIL REQUIREMENTSSymbols


aX, aY, aZ = longitudinal, transverse and vertical accelerations, in m/s2, at xG, yG, zG, as defined in Pt.3Ch.4 Sec.3 [3.2]

dsc = diameter, in m, of a steel coildshr = effective shear depth of the stiffener as defined in Pt.3 Ch.3 Sec.7 [1.4.3]Fsc‐ib‐s = static load on inner bottom, in kN, as defined in [2.3.1]Fsc‐ib = total load on inner bottom, in kN, as defined in [2.2.1]Fsc‐hs‐s = static load on hopper/inner side, in kN, as defined in [2.3.2]Fsc‐hs = total load on hopper/inner side, in kN, as defined in [2.2.2]hDB = height, in m, of the double bottom at the centreline, measured at mid-length of the cargo

hold, see Sec.2 [3.2.1]hHPL = vertical distance, in m, from the inner bottom at centreline to the upper intersection of

hopper tank and side shell or inner side for double side bulk carriers, determined at midlength of the considered cargo hold, as shown in Sec.2 [3.2.1]hHPL = 0 if there is no hopper tank

ℓ = distance, in m, between floorsℓlp = distance, in m, between outermost dunnage per elementary plate panel (EPP) in the ship x

direction, see Figure 3ℓst = length, in m, of a steel coilMsc‐ib = equivalent mass of a steel coil, in t, on inner bottom, as defined in [2.3.1]Msc‐hs = equivalent mass of a steel coil, in t, on hopper side, as defined in [2.3.2]n1 = number of tiers of steel coilsn2 = number of load points per EPP of the inner bottom, see [2.1.2]n3 = number of dunnages supporting one row of steel coilsR = vertical coordinate, in m, of the ship rotation centre, defined in Pt.3 Ch.4 Sec.3Tθ = roll period, in s, as defined in Pt.3 Ch.4 Sec.3 [2.1.1]VFull = volume, in m3, of cargo hold up to top of the hatch coaming:

VFull = VH + VHCW = mass, in t, of a steel coilx, y, z = x, y and y coordinates, in m, of the load point with respect to the reference coordinate

system defined in Pt.3 Ch.4 Sec.1 [1.2.1]φ = pitch angle, in deg, defined in Pt.3 Ch.4 Sec.3 [2.1.2]θ = roll angle, in deg, defined in Pt.3 Ch.4 Sec.3 [2.1.1]

θh = angle, in deg, between inner bottom plate and hopper sloping plate. In general θh is suchthat:



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1 Introduction

1.1 IntroductionShips may be loaded with steel coils on wooden dunnage. Such loading needs special consideration withadditional strength requirements that are outlined in this section.

1.2 ScopeThis section describes requirements for steel coil loading, including:

— steel coil loads in cargo holds, see [2]— hull local scantling, see [3].

1.3 ApplicationThe rules in this section apply to all ships loaded with steel coils on wooden dunnage. Ships assigned the shiptype notation Bulk carrier (with CSR) are exempted from these requirements.

2 Steel coil loads in cargo holds

2.1 General2.1.1 ApplicationIn Figure 1 typical loading of steel coils on wooden dunnage can be seen.It is assumed that all the steel coils have the same characteristics.In cases where steel coils are lined up in two or more tiers, formulae in [2.1.2] and [2.2] can be appliedassuming that only the lowest tier of steel coils is in contact with hopper sloping plate or inner side plate. Inother cases, scantling requirements shall be determined on a case-by-case basis.

Figure 1 Inner bottom loaded by steel coils

The two following arrangements of steel coils on the inner bottom are considered:

— the steel coils are positioned without respect to the location of the floors, as shown in Figure 2— the steel coils are positioned with respect to the location of the floors, as shown in Figure 3.



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2.1.2 Arrangement of steel coils independently of the floor locationsFor steel coils loaded without respect to the location of floors, see Figure 2:

— the number n2 of load point dunnages per EPP shall be found in Table 1— the distance ℓlp, in m, between outermost load point dunnages per EPP shall be found in Table 2.

Table 1 Number n2 of load point dunnages per EPP as a function of n3

n3n2

2 3 4 5

1

2

3

4

5

6

7

8

9

10



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Table 2 Distance between outermost load point dunnages per EPP, ℓlp, in m

n3n2

2 3 4 5

1 actual breadth of dunnages

2 0.5ℓst 0.33ℓst 0.25ℓst 0.2ℓst

3 1.2ℓst 0.67ℓst 0.50ℓst 0.4ℓst

4 1.7ℓst 1.20ℓst 0.75ℓst 0.6ℓst

5 2.4ℓst 1.53ℓst 1.20ℓst 0.8ℓst

6 2.9ℓst 1.87ℓst 1.45ℓst 1.2ℓst

7 3.6ℓst 2.40ℓst 1.70ℓst 1.4ℓst

8 4.1ℓst 2.73ℓst 1.95ℓst 1.6ℓst

9 4.8ℓst 3.07ℓst 2.40ℓst 1.8ℓst

10 5.3ℓst 3.60ℓst 2.65ℓst 2.0ℓst

n2 and

Figure 2 Steel coils loaded independently of floors locations

2.1.3 Arrangement of steel coils between floorsFor steel coils loaded with respect to the locations of floors, see Figure 3:

— the number n2 of load point dunnages per EPP shall be: n2 = n3— the distance ℓlp between outermost load point dunnages per EPP shall be equal to the distance betweenthe outermost dunnage supporting one row of steel coils.



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Figure 3 Steel coils loaded between floors

2.1.4 Centre of gravity of steel coil cargoThe position of the centre of gravity of the steel coil cargo of the considered cargo hold shall be calculated asfollows:

a) longitudinal positionxGsc is the x coordinate, in m, of the volumetric centre of gravity of the considered cargo hold withrespect to the reference coordinate system defined in Pt.3 Ch.4 Sec.1 [1.2.1].

b) transverse position

c) vertical position

where:

ε = coefficient shall be:

ε = 1.0 when a port side structural member is assessedε = -1.0 when a starboard side structural member is assessed.

2.2 Total loads2.2.1 Total load on the inner bottomThe total load Fsc-ib, in kN, due to steel coil cargoes on the inner bottom shall be:

but not less than 0

where:

Fsc‐ib‐s = static load, in kN, on the inner bottom, given in [2.3.1]Fsc‐ib‐d = dynamic load, in kN, on the inner bottom, given in [2.4.2]CXG, CYG = load combination factors, as defined in Pt.3 Ch.4 Sec.2 [2.2].

2.2.2 Total load on the hopper/inner sideThe total load Fsc-hs, in kN, due to steel coil cargoes on the hopper/inner side shall be:



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but not less than 0

where:

Fsc‐hs‐s = static load, in kN, on the hopper/inner side, given in [2.3.2]Fsc‐hs‐d = dynamic load, in kN, on the hopper/inner side, given in [2.4.3]CXG, CYG = load combination factors, as defined in Pt.3 Ch.4 Sec.2 [2.2].

2.3 Static loads2.3.1 Static loads on the inner bottomThe static load Fsc-ib-s, in kN, on the inner bottom due to steel coils shall be:

where:

Msc‐ib = equivalent mass of steel coils, in t, shall be:

for and

for or

KS = coefficient shall be:KS = 1.4 when steel coils are stowed in one tier with a key coilKS = 1.0 in other cases.

2.3.2 Static load on the hopper/inner sideThe static load Fsc-hs-s, in kN, on the hopper/inner side due to steel coils shall be:

where:

Msc‐hs = equivalent mass of steel coils, in t, shall be:

for and

for or

Ck = coefficient shall be:Ck = 3.2 when steel coils are stowed in two or more tiers, or when steel coils are stowed in onetier and a key coil is located 2nd or 3rd from hopper sloping plate or inner hull plateCk = 2.0 for other cases.



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2.4 Dynamic loads2.4.1 Tangential roll accelerationThe tangential roll acceleration aR, in m/s

2, shall be:

where:

yGsc = y coordinate, in m, of the centre of gravity of the steel coil cargo of the considered cargo hold,given in [2.1.4]

zGsc = z coordinate, in m, of the centre of gravity of the steel coil cargo of the considered cargo hold,given in [2.1.4].

2.4.2 Dynamic load on the inner bottomThe dynamic load Fsc-ib-d, in kN, on the inner bottom due to steel coils shall be:

where:

az = vertical acceleration, in m/s2, as defined in Pt.3 Ch.4 Sec.3 [3.2.3], calculated at the centre ofgravity of the steel coil cargo of the considered cargo hold, given in [2.1.4].

2.4.3 Dynamic load on the hopper/inner sideThe dynamic load Fsc-hs-d, in kN, on the hopper/inner side due to steel coils shall be:

where:

ε = coefficient defined in [2.1.4]CYS, CYR = load combination factors, defined in Pt.3 Ch.4 Sec.2 [2.2]asway = sway acceleration, in m/s2, as defined in Pt.3 Ch.4 Sec.3 [2.2.2]aR = tangential acceleration, in m/s2, as defined in [2.4.1]yGsc = y coordinate, in m, of the centre of gravity of the steel coil cargo of the considered cargo

hold, given in [2.1.4]zGsc = z coordinate, in m, of the centre of gravity of the steel coil cargo of the considered cargo

hold, given in [2.1.4].


3.1 General

3.1.1 The net thickness of inner bottom plating, hopper side plating and inner hull plating for ships intendedto carry steel coils shall comply with [3.3.1] and [3.4.1] up to a height not less than the one correspondingto the top of upper tier in touch with hopper or inner hull plating.



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The net section modulus and the net shear sectional area of longitudinal stiffeners on inner bottom, hoppertank top and inner hull for ships intended to carry steel coils shall comply with [3.3.2] and [3.4.2] up to aheight not less than the one corresponding to the top of upper tier in touch with hopper or inner hull plating.

3.2 Load application3.2.1 Design load setsThe static and dynamic load components shall be determined in accordance with the principal design loadscenarios given in Sec.2 [4].Radius of gyration, kr, and metacentric height, GM, shall be in accordance with Sec.2 [5.1.2] for theconsidered loading condition specified in the design load set. The design load sets for steel coil loading isgiven in Table 3.

Table 3 Design load sets

Structural memberDesignload set

Designload

scenarioLoad component Draught Acceptance

criteria

Loading conditionfor definitionof GM and kr

inner bottom, hoppersloping plate and inner hull BC-9 1 Fsc-ib-s or Fsc-hs-s TSC AC-I steel coil condition

inner bottom, hoppersloping plate and inner hull BC-10 2 Fsc-ib or Fsc-hs TSC AC-II steel coil condition

3.3 Inner bottom3.3.1 Inner bottom platingThe net thickness t, in mm, of plating of longitudinally stiffened inner bottom shall not be less than:

for design load set BC-9


where:

K1 = coefficient:

K2 = coefficient:

Ca = permissible bending stress coefficient, as defined in Pt.3 Ch.6 Sec.4 [1.1.1].



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3.3.2 Stiffeners of inner bottom platingThe net section modulus Z, in cm3, and the net web thickness, tw, in mm, of stiffeners located on innerbottom plating shall not be less than:

and for design load set BC-9


where:

K3 = coefficient as defined in Table 4

K3 = 2ℓbdg/3, when n2 > 10Cs = permissible bending stress coefficient, as defined in Pt.3 Ch.6 Sec.5 [1.1.2]Ct = permissible shear stress coefficient for the design load set being considered, shall be:

Ct = 0.85 for acceptance criteria set AC-ICt = 1.00 for acceptance criteria set AC-II

n2 = number of load points per EPP of the inner bottom, see [2.1].

Table 4 Coefficient K3

n2 1 2 3 4 5

K3

n2 6 7 8 9 10

K3

3.4 Hopper tank and inner hull3.4.1 Hopper side plating and inner hull platingThe net thickness t, in mm, of plating of longitudinally stiffened bilge hopper sloping plate and inner hull shallnot be less than:



where:

K1 = coefficient as defined in [3.3.1]



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Ca = as defined in [3.3.1].

3.4.2 Stiffeners of hopper side plating and inner hull platingThe net section modulus Z, in cm3, and the net web thickness, tw, in mm, of stiffeners located on bilgehopper sloping plate and inner hull plate shall not be less than:



where:

K3 = coefficient as defined in Table 4

K3 = 2ℓbdg/3 when n2 > 10Cs, Ct = as defined in [3.3.2].



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SECTION 4 ENHANCED FLOODED REQUIREMENTSSymbols

For symbols not defined in this section, see Pt.3 Ch.1 Sec.4 [2] and Sec.2.

D1 = distance, in m, from the baseline to the freeboard deck at side amidships

FR = resultant force, in kN, as defined in Table 5

hLS = mean height, in m, of the lower stool, measured from the inner bottom

KC‐f = coefficient:

Msw‐f = permissible vertical still water bending moment in flooded condition, in kNm, at the hulltransverse section being considered in hogging and sagging, as defined in [2.1.1]

Mwv = vertical wave bending moment in seagoing condition, in kNm, at the hull transverse sectionbeing considered in hogging and sagging, as defined in Pt.3 Ch.4 Sec.4 [3.1]

perm = permeability of cargo, shall be:perm = 0.3 for iron ore, coal cargoes and cementperm = 0 for steel coils

PR = resultant pressure, in kN/m2, as defined in Table 5

Qsw‐f = positive and negative permissible vertical still water shear force in flooded condition, in kN, atthe hull transverse section being considered, as defined in [2.1.1]

Qwv = positive and negative vertical wave shear force in seagoing condition, in kN, at the hulltransverse section being considered, as defined in Pt.3 Ch.4 Sec.4 [3.2]

Qsw‐Lcd‐f = vertical still water shear force in flooded condition, in kN, at the hull transverse section beingconsidered, for a seagoing loading condition defined in the loading manual being floodedaccording to [2.1.2]

sC = half pitch, in mm, of the corrugation flange as defined in Pt.3 Ch.3 Sec.6 Figure 10

ZB‐gr = gross section modulus, in m3, at bottom, shall be calculated according Pt.3 Ch.5 Sec.2 [1.2.1]

ZD‐gr = gross section modulus, in m3, at deck, shall be calculated according Pt.3 Ch.5 Sec.2 [1.2.2]

ρc = density of bulk cargo, in t/m3, as defined in [2.2.5].

1 Introduction

1.1 IntroductionThis section provides enhanced flooded requirements for ships intended for carriage of heavy dry bulk cargo.

1.2 ScopeThis section describes enhanced flooded requirements for dry cargo ships in addition to the requirementsdescribed in Pt.3, including:

— hull girder loads, pressures and forces due to dry cargoes in flooded conditions, see [2]— transverse vertically corrugated watertight bulkheads in flooded condition, see [3]— allowable hold loading in flooded conditions, see [4]



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— hull girder strength in flooded conditions, see [5].

1.3 ApplicationThe requirements in this section apply to the ships with the class notation listed in Sec.2 [6.3].

2 Hull girder loads, pressures and forces due to dry cargoes inflooded conditions

2.1 Vertical still water hull girder loads2.1.1 Flooded conditionsThe designer shall provide the permissible still water bending moment Msw-f and shear force Qsw-f in floodedcondition. Each cargo hold shall be considered individually flooded to the equilibrium waterline.The permissible vertical still water bending moment and shear force in flooded condition at sea at anylongitudinal position shall envelope the most severe flooded seagoing loading conditions defined in theloading manual, i.e. all seagoing loaded and ballast conditions. Flooding check of harbour conditions, dockingcondition afloat, loading/unloading sequences and ballast water exchange are not applicable.

2.1.2 Flooding criteriaTo calculate the mass of water ingress, the following assumptions shall be made:

— the permeability of empty cargo spaces and volume left in loaded cargo spaces above any cargo shall be0.95

— appropriate values of permeability and bulk density shall be used for any cargo carried. For iron ore, aminimum permeability of 0.3 with a corresponding bulk density of 3.0 t/m3 shall be used. For cement, aminimum permeability of 0.3 with a corresponding bulk density of 1.3 t/m3 shall be used. In this respect,permeability for solid bulk cargo means the ratio of the floodable volume between the particles, granulesor any larger pieces of the cargo, to the gross volume of the bulk cargo.

For packed cargo conditions (such as steel mill products), the actual density of the cargo shall be used with apermeability of zero.

2.2 Vertically corrugated transverse watertight bulkheads2.2.1 ApplicationThe pressure defined in this subsection applies to vertically corrugated transverse watertight bulkheads of thecargo holds of dry cargo ships for the assessment in flooded conditions.Each cargo hold shall be considered individually flooded, see Figure 1, Figure 2 and Figure 3.

2.2.2 GeneralThe loads to be considered as acting on each bulkhead are those given by the combination of loadsinduced by cargo loads with those induced by the flooded loads of one hold adjacent to the bulkhead underexamination. In any case, the pressure due to the flooded loads without cargo shall also be considered.The most severe combinations of cargo induced loads and flooded loads shall be used for the check of thescantlings of each bulkhead, depending on the loading conditions included in the loading manual consideringthe individual flooded condition of both loaded and empty holds:

— homogeneous loading conditions— non-homogeneous loading conditions.

For the purpose of this section, the following items are defined as:



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— design load limits:the specified design load limits for the cargo holds shall be represented by loading conditions defined bythe designer in the loading manual

— maximum cargo mass to consider:unless the ship is intended to carry, in non-homogeneous conditions, only iron ore or cargo having bulkdensity equal to or greater than 1.78 t/m3, the maximum mass of cargo which may be carried in the holdshall also be considered to fill that hold up to the top of the hatch coaming

— homogeneous loading conditions:homogeneous loading condition means a loading condition in which the ratio between the highest and thelowest filling level, evaluated for each hold, does not exceed 1.20; it shall be corrected for different cargodensities

— packed cargoes:holds carrying packed cargoes (such as steel mill products) shall be considered as empty

— unconsidered loading conditions:non-homogeneous part loading conditions associated with multi-port loading and unloading operations forhomogeneous loading conditions are not mandatory for the verification of these requirements.

2.2.3 Flooded levelThe flooded level zF is the distance, in m, measured vertically from the baseline with the ship in the uprightposition, and obtained from Table 1.

Table 1 Flooded level zF, in m, for vertically corrugated transverse bulkheads

Vertically corrugated transverse bulkhead positionShip type

foremost others

zF = 0.95 D1 zF = 0.85 D1Dry cargo ships with less than 50,000 t deadweightwith Type B freeboard

zF = 0.9 D11) zF = 0.8 D1

1)

zF = D1 zF = 0.9 D1Other dry cargo ships

zF = 0.95 D11) zF = 0.85 D1

1)

1) For ships carrying cargoes having bulk density less than 1.78 t/m3 in non-homogeneous loading conditions.

2.2.4 Flooded patternsThree different flooded patterns shall be considered:

— the flooded level is below the upper surface of the cargo, see Figure 1: zC > zF— the flooded level is above the upper surface of the cargo, see Figure 2: zC ≤ zF— the flooded hold is empty, see Figure 3: zC = hDB.



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Figure 1 Flooded level below upper surface of bulk cargo

Figure 2 Flooded level above upper surface of bulk cargo



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Figure 3 Flooded cargo hold without cargo

2.2.5 Mass and density in flooded conditionThe dry cargo mass and the density of the cargo shall be as defined in Table 2.



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Table 2 Dry bulk cargo mass and density for strength assessment in flooded condition

Homogeneous loading condition Alternate loading condition

Ship type Cargo massCargo density fully filled hold partially

filled hold fully filled hold partiallyfilled hold

hold loaded withρC ≤ 1.78 t/m

2)

M M = MH M = MH

HC(B)ρC ρC = 3.0

1) N/A

M M = MH M = MH M = MHD M = MHD M = MHD

HC(A)ρC ρC = 3.0

1) ρC = 3.0 1) ρC = 1.78

M M = MH M = MH M = 1.2 MFull M = 1.2 MFull M = 1.2 MFull

HC(B*)ρC ρC = 3.0

1) ρC = 3.0 1) ρC = 1.78

M M = MH M = MH M = MHD M = MHD M = MHD

HC(M)3)ρC

maximumvalue specifiedin the loadingmanual

maximumvalue specifiedin the loadingmanual

ρC = 1.78

M M = MH M = MH

OC(H)ρC ρC = 3.0

N/A

M M = MH M = MH M = MH M = MH

OC(M)ρC ρC = 3.0 ρC = 3.0

N/A

1) Shall be 3.0 unless an alternative maximum allowable cargo density is specified in the loading manual. In suchcases, the maximum density of the cargo that the ship is allowed to carry shall be indicated within the additionalnotation Maximum cargo density (x.y t/m3) as defined in Pt.1 Ch.2.

2) Shall be applied for bulk carriers that are required to carry cargoes with a density less than or equal to 1.78 t/m3.3) Alternate loading conditions are only applicable if such conditions are included in the loading manual.

2.2.6 Pressures and forces on vertically corrugated transverse bulkheads of flooded cargo holdsThe static pressure Pbf-s, in kN/m

2, at any point of the vertically corrugated transverse bulkhead located at alevel z from the baseline is given in Table 3 for each flooded pattern defined in [2.2.4].

The force Fbf-s, in kN, acting on a corrugation of a transverse bulkhead is given by Table 4 for each floodedpattern defined in [2.2.4], where:

Pbf‐s‐LE = static pressure calculated according to Table 1 for z = hLS + hDB.



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Table 3 Static pressure on vertically corrugated transverse bulkhead of a flooded cargo hold Pbf-s

Flooded case Load calculationpoint Pressure Pbf-s, in kN/m

2

z > zC

zC ≥ z ≥ zF

zF > z ≥ hDB

z > zF

zF ≥ z ≥ zCPbf-s = ρg (zF – z)

zC > z ≥ hDB

Table 4 Force acting on a corrugation in the flooded cargo holds Fbf-s

Flooded case Force Fbf-s, in kN

zC > zF

zF ≥ zC

2.2.7 Pressures and forces on vertically corrugated transverse bulkheads of non-flooded cargoholdsThe static pressure Pbs, in kN/m

2, at a point of the vertically corrugated transverse bulkhead, located at thelevel z from the baseline, due to dry bulk cargo in a non-flooded cargo hold transverse bulkhead, which isflooded on the other side, shall be:

but not less than 0.

The resultant force Fbs, in kN, acting on a corrugation shall be:

2.2.8 Resultant pressures and forces on vertically corrugated transverse bulkheads of floodedcargo holdsThe resultant pressure PR, in kN/m

2, at each point of the bulkhead, and the resultant force FR, in kN, actingon a corrugation, given in Table 5, shall be considered for the assessment in flooded conditions of verticallycorrugated transverse bulkhead structures, where:

Pbf‐s = pressure in the flooded cargo holds, in kN/m2, as defined in [2.2.6]Pbs = pressure in the non-flooded cargo holds, in kN/m2, as defined in [2.2.7]Fbf‐s = force acting on a corrugation in the flooded cargo holds, in kN, as defined in [2.2.6]



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Fbs = force acting on a corrugation in the non-flooded cargo holds, in kN, as defined in [2.2.7].

Table 5 Resultant pressure PR and resultant force FR on vertically corrugated transverse bulkheadin flooded condition

Loading condition Resultant pressure PR, in kN/m2 Resultant force FR, in kN Application

homogeneous PR = Pbf-s – 0.8 Pbs FR = Fbf-s – 0.8 Fbs in general 2)

alternate PR = Pbf-s FR = Fbf-sHC(A), HC(B*),

HC(M) 1) and OC(M)

1) Alternate loading conditions are only applicable if such conditions are included in the loading manual.2) Loading conditions in which the ratio between hc, evaluated for each hold, does not exceed 1.2.

2.3 Double bottom in cargo hold region in flooded conditions2.3.1 GeneralThe loads to be considered as acting on the double bottom are those given by the external sea pressures andthe combination of the cargo loads with those induced by the flooding of the hold to which the double bottombelongs.The most severe combinations of cargo induced loads and flooded loads shall be used, depending on theloading conditions included in the loading manual:

— homogeneous loading conditions— non-homogeneous loading conditions— packed cargo conditions (such as in the case of steel mill products).

For each loading condition, the maximum allowable dry bulk cargo density shall be determined in calculatingthe allowable hold loading.

2.3.2 Flooded levelThe flooded level zF is the distance, in m, measured vertically from the baseline with the ship in the uprightposition, and obtained from Table 6.

Table 6 Flooded level zF, for double bottom in cargo hold region

Cargo holdShip type

foremost others

dry cargo ships with less than 50,000 t deadweight with type B freeboard zF = 0.95 D1 zF = 0.85 D1

other dry cargo ships zF = D1 zF = 0.9 D1



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3 Transverse vertically corrugated watertight bulkheads separatingcargo holds in flooded condition

3.1 Structural arrangement3.1.1 GeneralFor ships of 190 m of length L and above, the transverse vertically corrugated watertight bulkheads shall befitted with a lower stool, and generally with an upper stool below deck. For ships having length L less than190 m, corrugations may extend from inner bottom to deck.

3.1.2 Lower stoolThe lower stool, when fitted, shall have a height in general not less than three (3) corrugation depths.The ends of stool side ordinary stiffeners, when fitted in a vertical plane, shall be attached to brackets at theupper and lower ends of the stool. Lower stool side vertical stiffeners and their brackets in the stool shall bealigned with the inner bottom structures such as longitudinals or similar. Lower stool side plating shall not beknuckled anywhere between the inner bottom plating and the stool top plate.The distance d from the edge of the stool top plate to the surface of the corrugation flange shall be inaccordance with Figure 4.The lower stool shall be installed in line with double bottom floors or girders as the case may be, and shallhave a width not less than 2.5 corrugation depths.The stool shall be fitted with diaphragms in line with the longitudinal double bottom girders or floors. Scallopsin the brackets and diaphragms in way of the connections to the stool top plate shall be avoided.The stool side plating shall be connected to the stool top plate and the inner bottom plating by either fullpenetration or partial penetration welds. The supporting floors shall be connected to the inner bottom byeither full penetration or partial penetration welds.

Figure 4 Permitted distance, d, from the edge of the stool top plate to the surface of thecorrugation flange



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3.1.3 Upper stoolThe upper stool, when fitted, shall have a height between two and three times the corrugation depth.Rectangular stools shall have a height in general equal to twice the depth of corrugations, measured from thedeck level and at the hatch side girder. Brackets or deep webs shall be fitted to connect the upper stool to thedeck transverse or hatch end beams.The upper stool of a transverse bulkhead shall be properly supported by deck girders or deep bracketsbetween the adjacent hatch end beams. The width of the upper stool bottom plate shall generally be thesame as that of the lower stool top plate. The stool top of non-rectangular stools shall have a width not lessthan twice the depth of corrugations. The ends of stool side ordinary stiffeners when fitted in a vertical plane,shall be attached to brackets at the upper and lower end of the stool.The stool shall be fitted with diaphragms in line with and effectively attached to longitudinal deck girdersextending to the hatch end coaming girders or transverse deck primary supporting members. Scallops in thebrackets and diaphragms in way of the connection to the stool bottom plate shall be avoided.

3.2 Net thickness of corrugation3.2.1 Cold formed corrugationThe net plate thickness t, in mm, of transverse vertically corrugated watertight bulkheads separating cargoholds shall not be less than:

where:

sCW = plate width, in mm, equal to the width of the corrugation flange a or the web c, whichever is greateras defined in Pt.3 Ch.3 Sec.6 Figure 10.

3.2.2 Built-up corrugationWhere the thicknesses of the flange and web of built-up corrugations of transverse vertically corrugatedwatertight bulkheads separating cargo holds are different, the net plate thicknesses shall not be less thanthat obtained from the following formula.

The net thickness tN, in mm, of the narrower plating shall not be less than:

sN = plate width, in mm, of the narrower plating.

The net thickness tW, in mm, of the wider plating shall not be less than the greater of the following formulae:

where:

tNO = net offered thickness of the narrower plating, in mm, shall not be greater than:



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3.2.3 Span of corrugationsThe span lC of the corrugations shall be taken as the distance shown in Figure 5.For the bottom of the upper stool, lC shall not be taken greater than the distance from the upper deck at thecenter line equal to:

— 3 times the depth of corrugation, for non rectangular upper stool

— 2 times the depth of corrugation, for rectangular upper stool.For the non-rectangular upper stool where stool sides are in line with hatch end coamings at upperdeck level, the above limitation for the distance of the upper stool bottom from the upper deck may bedisregarded.

3.2.4 Lower part of corrugationThe net thickness of the lower part of corrugations shall be maintained for a distance of not less than 0.15 ℓCmeasured from the top of the lower stool, or from the inner bottom where no lower stool is fitted.

3.2.5 Middle part of corrugationThe net thickness of the middle part of corrugations shall be maintained for a distance not greater than 0.3 ℓCfrom the upper end of lC.

Figure 5 Parts of corrugation



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3.3 Bending, shear and buckling check3.3.1 Bending capacity and shear capacityThe bending capacity and the shear capacity of the corrugations of transverse watertight corrugatedbulkheads separating cargo holds shall comply with the following formulae:

where:

M = bending moment in a corrugation, in kNm:

FR = resultant force, in kN, given in [2.2.8]

lC = span of the corrugations, in m, as given in [3.2.3]

WLE = net section modulus, in cm3, of one half pitch corrugation at the lower end of the corrugationsaccording to [3.4], shall not be greater than:

WG = net section modulus, in cm3, of one half pitch corrugation, in way of the upper end of shedder orgusset plates, as applicable, according to [3.4]

Q = shear force, in kN, at the lower end of a corrugation, shall be:

hG = height, in m, of shedders or gusset plates, as applicable as shown in Figure 6 to Figure 8

PR = resultant pressure, in kN/m2, in way of the middle of the shedders or gusset plates, as applicable,according to [2.2.8]

WM = net section modulus, in cm3, of one half pitch corrugation, at the mid-span of corrugationsaccording to [3.4], but not greater than 1.15 WLE

τ = shear stress, in N/mm2, in the corrugation:

Ashr = net shear area, in cm2, of one half pitch corrugation. The calculated net shear area shall considerpossible reduced shear efficiency due to non-straight angles between the corrugation webs andflanges. In general, the reduced shear area may be obtained by multiplying the web sectional areaby sin φ

φ = angle between the web and the flange, see Pt.3 Ch.3 Sec.6 Figure 10.

The net section modulus of the corrugations in the upper part of the bulkhead, as defined in Figure 5, shallnot be less than 75% of that of the middle part complying with this requirement, corrected for differentminimum yield stresses.



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3.3.2 Shear buckling check of the bulkhead corrugation websThe shear stress, τ, calculated according to [3.3.1], shall comply with the following formula:

τ ≤ τC

where:

τC = critical shear buckling stress, in N/mm2, shall be:

for

for

τE = Euler shear buckling stress, in N/mm2, shall be:

kt = coefficient, shall be equal to 6.34tw = net thickness, in mm, of the corrugation websc = width, in mm, of the corrugation webs as shown in Pt.3 Ch.3 Sec.6 Figure 10.

3.4 Net section modulus at the lower end of the corrugations3.4.1 Effective flange widthThe net section modulus at the lower end of the corrugations shall be calculated with the compression flangehaving an effective flange width beff not larger than the following formula:

where:

CE = coefficient shall be equal to:

for β > 1.25

for β ≤ 1.25

β = coefficient shall be equal to:

a = width, in mm, of the corrugation flange as shown in Pt.3 Ch.3 Sec.6 Figure 10tf = net flange thickness, in mm.

3.4.2 Webs not supported by local bracketsUnless welded to a sloping stool top plate as defined in [3.4.5], if the corrugation webs are not supported bylocal brackets below the stool top plate (or below the inner bottom) in the lower part, the section modulus ofthe corrugations shall be calculated considering the corrugation webs 30% effective.



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3.4.3 Effective shedder platesProvided that effective shedder plates are fitted as shown in Figure 6, when calculating the section modulusat the lower end of the corrugations (sections 1 in Figure 6), the net area, in cm2, of flange plates may beincreased by ISH:

but lower than 2.5 a tf ·10-3

where:

a = width, in mm, of the corrugation flange as shown in Pt.3 Ch.3 Sec.6 Figure 10tSH = net shedder plate thickness, in mmtf = net flange thickness, in mm.

Effective shedder plates are those which:

— are not knuckled— are welded to the corrugations and the lower stool top plate according to Pt.3 Ch.13 Sec.1 [2.4.5]— are fitted with a minimum slope of 45°, their lower edge being in line with the lower stool side plating— have thickness not less than 75% of that required for the corrugation flanges— have material properties not less than those required for the flanges.

Figure 6 Symmetrical and unsymmetrical shedder plates



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Figure 7 Symmetrical and unsymmetrical gusset/shedder plates

Figure 8 Asymmetrical gusset/shedder plates

3.4.4 Effective gusset platesProvided that effective gusset plates are fitted, when calculating the section modulus at the lower end of thecorrugations (sections 1 in Figure 7 and Figure 8), the net area, in cm2, of flange plates may be increased bythe factor IG:

where:

hG = height, in m, of gusset plates as shown in Figure 7 and Figure 8 but lower than:



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SGU = width, in m, of gusset platestf = net flange thickness, in mm.

Effective gusset plates are those which:

— are in combination with shedder plates having thickness, material properties and welded connections asrequested for shedder plates in [3.4.3]

— have a height not less than half of the flange width— are fitted in line with the lower stool side plating— are welded to the lower stool top plate, corrugations and shedder plates according to Pt.3 Ch.13 Sec.1[2.4.5]

— have thickness and material properties not less than those required for the flanges.

3.4.5 Corrugation web efficiency in way of sloping stool top plateWhere the corrugation webs are welded to a sloping stool top plate which has an angle not less than 45º withthe horizontal plane, the section modulus at the lower end of the corrugations may be calculated consideringthe corrugation webs fully effective. For angles less than 45º, the effectiveness of the web may be obtainedby linear interpolation between 30% efficient for 0º and 100% efficient for 45º.Where effective gusset plates are fitted, when calculating the net section modulus of corrugations, the netarea of flange plates may be increased as specified in [3.4.4] above. No credit will be given to shedder platesonly.

3.5 Supporting structure in way of corrugated bulkheads3.5.1 Lower stool

a) The net thickness of the stool top plate shall not be less than that required for the attached corrugatedbulkhead and shall be of at least the same material yield strength as the attached corrugation. Theextension of the top plate beyond the corrugation shall not be less than the as-built flange thickness ofthe corrugation.

b) The net thickness of the stool side plate, within the region of the corrugation depth from the stool topplate, shall not be less than the corrugated bulkhead flange net required thickness at the lower endand shall be of at least the same material yield strength. The net thickness may be reduced to 90%of corrugation flange thickness if continuity is provided between the corrugation web and supportingbrackets inside the stool as defined in c).

c) Continuity between corrugation web and lower stool supporting brackets shall be maintained inside thestool. Alternatively, lower stool supporting brackets inside the stool shall be aligned with every knucklepoint of corrugation web.

d) The net thickness of supporting bracket shall not be less than 80% of the required net thickness of thecorrugation webs and shall be of at least the same material yield strength.

e) The net thickness of supporting floors shall not be less than the net required thickness of the stool sideplating (excluding the application of Grab requirements as defined in Pt.6 Ch.1 Sec.1) connected tothe inner bottom and shall be of at least the same material yield strength. If material of different yieldstrength is used, the required thickness shall be adjusted by the ratio of the two material factors k.

f) Where a lower stool is fitted, particular attention shall be given to the through-thickness properties, andarrangements for continuity of strength, at the connection of the bulkhead stool to the inner bottom. Forrequirements for plates with specified through-thickness properties, see Pt.3 Ch.3 Sec.1 [2.5].

3.5.2 Upper stool

a) The net thickness of the stool bottom plate shall not be less than that required for the attachedcorrugated bulkhead and shall be of at least the same material yield strength as the attachedcorrugation. The extension of the top plate beyond the corrugation shall not be less than the as-builtflange thickness of the corrugation.



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b) The net thickness of the lower portion of stool side plating shall not be less than 80% of the upper partof the bulkhead plating as required by [3.2], where the same material is used. If material of differentyield strength is used, the required thickness shall be adjusted by the ratio of the two material factors k.

3.5.3 Local supporting structure in way of corrugated bulkheads without a lower stool

a) The net thickness of the supporting floors and pipe tunnel beams in way of a corrugated bulkhead shallnot be less than the required net required thickness of the corrugation flanges and shall be of at leastthe same material yield strength. The inner bottom and hopper tank in way of the corrugation shall beof at least the same material yield strength as the attached corrugation, and Z grade steel as defined inPt.3 Ch.3 Sec.1 [2.5] shall be used unless through thickness properties are documented.

b) Brackets/carlings arranged in line with the corrugation web shall have a depth of not less than 0.5 timesthe corrugation depth and a net thickness not less than 80% of the net thickness of the corrugation websand shall be of at least the same material yield strength. Where support is provided by gussets withshedder plates instead of brackets/carlings, the height of the gusset plate, see hG in Figure 6, shall beat least equal to the corrugation depth. The gusset plates shall be fitted in line with and between thecorrugation flanges. The net thickness of the gusset and shedder plates shall not be less than 100%and 80%, respectively, of the net thickness of the corrugation flange and shall be of at least the samematerial yield strength.

c) The plating of supporting floors shall be connected to the inner bottom by either full penetration orpartial penetration weld.

3.6 Upper and lower stool subject to lateral flooded pressure3.6.1 Yielding check of platingThe net thickness, t in mm, of upper and lower stool plating shall not be less than required in Pt.3 Ch.6 Sec.4[1.1], applying acceptance criteria AC-III and pressure Pbf-s, in kN/m

2, according to [2.2.6].

3.6.2 Yielding check of stiffenersThe minimum net web thickness, in mm, and the minimum net section modulus, in cm3, shall not be lessthan required in Pt.3 Ch.6 Sec.5 [1.1], applying acceptance criteria AC-III and pressure Pbf-s, in kN/m

2,according to [2.2.6].

3.7 Corrosion addition3.7.1 GeneralThe total corrosion addition, in mm, shall comply with the requirements given in Pt.3 Ch.3 Sec.3, but not lessthan the minimum corrosion addition given in [3.7.2].

3.7.2 Minimum corrosion additionThe minimum total corrosion addition, in mm, for both sides of the structural member shall be:

4 Allowable hold loading in flooded conditions

4.1 Evaluation of double bottom capacity and allowable hold loading4.1.1 Shear capacity of the double bottomThe shear capacity of the double bottom shall be calculated as the sum of the shear strength at each end of:

— floors connected to hopper tanks, less one half of the shear strength of the two floors adjacent to eachstool, or transverse bulkhead if no stool is fitted as shown in Figure 9. The shear strength of floors shall becalculated according to [4.1.2]



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— double bottom girders connected to stools, or transverse bulkheads if no stool is fitted. The shear strengthof girders shall be calculated according to [4.1.3].

The floors and girders to be considered when calculating the shear capacity of the double bottom are thoseinside the hold boundaries formed by the hopper tanks and stools or transverse bulkheads if no stool is fitted.Where both ends of girders or floors are not directly connected to the hold boundaries, their strength shall beevaluated for the connected end only.The hopper tank side girders and the floors directly below the connection of the stools or transversebulkheads if no stool is fitted to the inner bottom may not be included.For special double bottom designs, the shear capacity of the double bottom shall be calculated by means ofdirect calculations carried out in accordance with requirements specified in Pt.3 Ch.7, as applicable.

4.1.2 Floor shear strengthThe floor shear strength, in kN, shall be as given in the following formulae:

— in way of the floor panel adjacent to the hopper tank:

— in way of the openings in the outermost bay (i.e. that bay which is closer to the hopper tank):

where:

Af = net sectional area, in mm2, of the floor panel adjacent to the hopper tankAf,h = net sectional area, in mm2, of the floor panels in way of the openings in the outermost bay (i.e. the

bay which is closer to the hopper tank)

τA = allowable shear stress, in N/mm2, shall equal the lesser of:

and

for floors adjacent to the stools or transverse bulkheads, τA is:

t = floor web net thickness, in mms = spacing, in m, of stiffening members of the panel consideredη1 = coefficient shall be equal to 1.1η2 = coefficient shall be equal to 1.2. It may be reduced to 1.1 where appropriate reinforcements are

fitted in way of the openings in the outermost bay, upon examination by the Society on a case-by-case basis.

4.1.3 Longitudinal girder shear strengthThe longitudinal girder shear strength, in kN, shall be as given in the following formulae:

— in way of the longitudinal girder panel adjacent to the stool or transverse bulkhead, if no stool is fitted:



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— in way of the largest opening in the outermost bay (i.e. that bay which is closer to the stool) or transversebulk-head, if no stool is fitted:

Ag = net sectional area, in mm2, of the longitudinal girder panel adjacent to the stool (or transversebulkhead, if no stool is fitted)

Ag,h = net sectional area, in mm2, of the longitudinal girder panel in way of the largest opening in theoutermost bay (i.e. that bay which is closer to the stool) or transverse bulkhead, if no stool is fitted

τA = allowable shear stress, in N/mm2, as defined in [4.1.2] where tN is the girder web net thicknessη1 = coefficient shall be equal to 1.1η2 = coefficient shall be equal to 1.15. It may be reduced to 1.1 where appropriate reinforcements are

fitted in way of the largest opening in the outermost bay, upon examination by the Society on acase-by-case basis.

4.1.4 Allowable hold loadingThe maximum mass of cargo in any cargo hold as given in the loading manual shall be less than theallowable hold loading, in t, shall be:

where:

ρC = density of the dry bulk cargo, in t/m3, as defined in [2.2.5]V = volume, in m3, occupied by the cargo up to the level hBF = coefficient shall be:

F = 1.1 in generalF = 1.05 for steel mill products

hB = level of cargo, in m, shall be:

P = pressure, in kN/m2, shall be:

— for dry bulk cargoes, the lesser of:

— for steel mill products:

D1 = distance, in m, from the baseline to the freeboard deck at side amidshipshF = inner bottom flooded height, in m, measured vertically with the ship in the upright position, from

the inner bottom to the flooded level zFzF = flooded level, in m, as defined in [2.3.2]perm = permeability of cargo, may be lower than 0.3

Z = pressure, in kN/m2, shall be equal to the lesser of:



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CH = shear capacity of the double bottom, in kN, calculated according to [4.1.1], considering, for eachfloor, the lesser of the shear strengths Sf1 and Sf2 as defined in [4.1.2] and, for each girder, thelesser of the shear strengths Sg1 and Sg2 as defined in [4.1.3]

ADB,H = area, in m2:

CE = shear capacity of the double bottom, in kN, calculated according to [4.1.1], considering, for eachfloor, the shear strength Sf1 as defined in [4.1.2] and, for each girder, the lesser of the shearstrengths Sg1 and Sg2 as defined in [4.1.3]

ADB,E = area, in m2:

n = number of floors between stools or transverse bulkheads, if no stool is fittedSi = space of i-th floor, in mBDB,i = length, in m, shall be equal to:

BDB,i = BDB - s for floors for which Sf1 < Sf2BDB,i = BDB,h for floors for which Sf1 ≥ Sf2

BDB = breadth, in m, of double bottom between the hopper tanks as shown in Figure 10BDB,h = distance, in m, between the two openings considered as shown in Figure 10s = spacing, in m, of inner bottom longitudinal ordinary stiffeners adjacent to the hopper tanks.



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Figure 9 Double bottom structure

Figure 10 Dimensions BDB and BDB,h

5 Vertical hull girder bending and shear strength in floodedconditions

5.1 Vertical hull girder bending strength5.1.1 GeneralThe vertical hull girder bending strength requirements given in Pt.3 Ch.5 Sec.2 [1] shall be complied withusing detailed requirements given in the following subsections.

5.1.2 Permissible still water bending moments for flooded conditionsThe permissible still water bending moments, in kNm, for flooded conditions in hogging and sagging shallcomply with the following criteria:

where:



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Msw = permissible vertical still water bending moment, in kNm, for hogging and sagging, in seagoingcondition at the hull transverse section being considered as defined in Pt.3 Ch.4 Sec.4 [2.2.2].The bending moment Mwv used above shall have the same sign as the considered bending momentMsw-f.

5.2 Vertical hull girder shear strength of bulk carriers5.2.1 Design criteria in flooded conditionsThe positive and negative permissible vertical still water shear force, in kN, in flooded conditions shall complywith the following criteria:

where:

Qsw = permissible vertical still water shear force, in kN, positive and negative, in seagoing condition atthe hull transverse section being considered as defined in Pt.3 Ch.4 Sec.4 [2.4.2].

The shear force Qwv used above shall have the same sign as the considered shear force Qsw-f.

The vertical still water shear forces, in kN, for all loading conditions in flooded conditions, shall comply withthe following criteria:

where:

ΔQmdf = shear force correction, in kN, as defined in Sec.5 [5.2.4], in flooded conditions.

The shear force Qsw-f used above shall have the same sign as the considered shear force Qsw-Lcd-f.

5.3 Vertical hull girder shear strength of ore carriers5.3.1 Design criteria in flooded conditionsThe positive and negative permissible vertical still water shear force, in kN, in flooded conditions shall complywith the following criteria:

where:

Qsw = permissible vertical still water shear force, in kN, positive and negative, in seagoing condition atthe hull transverse section being considered as defined in Pt.3 Ch.4 Sec.4 [2.4.2].

The shear force Qwv used above shall have the same sign as the considered shear force Qsw-f.

The vertical still water shear forces, in kN, for all loading conditions in flooded conditions, shall comply withthe following criteria:

The shear force Qsw-f used above shall have the same sign as the considered shear force Qsw-Lcd-f.



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5.4 Hull girder ultimate strength check5.4.1 GeneralIn addition to the hull girder ultimate strength check requirements given in Pt.3 Ch.5 Sec.4 for intactconditions, the same hull girder ultimate strength requirement applies to flooded conditions using hull girderultimate bending loads in accordance with [5.4.2].

5.4.2 Hull girder ultimate bending loadsThe vertical hull girder bending moment in hogging and sagging conditions, in kNm, to be considered in theultimate strength check shall be:

where:

γS = partial safety factor for the still water bending moment, shall be in accordance with Pt.3 Ch.5Sec.4 [2.2.1]

γW = partial safety factor for the vertical wave bending moment, shall be in accordance with Pt.3 Ch.5Sec.4 [2.2.1]. Pa

rt 5 Chapter 1 Section 4


DNV AS

SECTION 5 GENERAL DRY CARGO SHIPS AND MULTI-PURPOSE DRYCARGO SHIPSSymbols


aY = transverse acceleration, in m/s2, at the centre of gravity of the block load, for the consideredload case, shall be obtained according to Pt.3 Ch.4 Sec.3 [3.2.2]

aZ = vertical acceleration, in m/s2, at the centre of gravity of the block load, for the consideredload case, shall be obtained according to Pt.3 Ch.4 Sec.3 [3.2.3]

BtweenDk = breadth of the cargo hold, in m, measured in way of the tweendeck hatch coversBTop = breadth of the cargo hold, in m, measured in way of the weather deck hatch coversfhar‐M = wave correction factor for permissible vertical still water bending moment for harbour/

sheltered water operation, shall be:

fhar‐M = 0.5 in generalfhar‐Q = wave correction factor for permissible vertical still water shear force for harbour/sheltered

water operation, shall be:

fhar‐Q = 0.5 in generalℓp = length of hatch cover, in m, in longitudinal directionΔz = distance between the cargo's centre of gravity on hatch cover and the stopper locations, in m,

in vertical directionMH = cargo mass, in t, as defined in Sec.2MIB = maximum block cargo mass, in t, on inner bottom in way of a cargo hold according to the

design load planMDeck = maximum block cargo mass, in t, on weather deck hatch covers in way of a cargo hold

according to the design load planMtweenDk = maximum block cargo mass, in t, on tween deck hatch covers in way of a cargo hold

according to the design load planMsw = permissible vertical still water bending moment for seagoing operation, in kNm, for hogging

and sagging respectively at the hull transverse section being considered, as defined in Pt.3Ch.4 Sec.4 [2.2.2]

Msw‐p = permissible vertical still water bending moment for harbour/sheltered water operation, inkNm, for hogging and sagging respectively at the hull transverse section being considered, asdefined in Pt.3 Ch.4 Sec.4 [2.2.3]

Mwv = vertical wave bending moment for seagoing operation, in kNm, for hogging and saggingrespectively at the hull transverse section being considered, as defined in Pt.3 Ch.4 Sec.4[3.1]

Pdl‐s = static pressure, in kN/m2, due to distributed load on exposed decks as defined in Pt.3 Ch.4Sec.5 [2.3.1], and static pressure, in kN/m2, due to distributed load on inner bottom andtween decks as defined in Pt.3 Ch.4 Sec.6 [2.2.1]

PC = static uniform cargo load, in kN/m2, due to cargo loads on weather deck hatch covers, asdefined in Pt.3 Ch.12 Sec.4 [2.3.1]

TB = deepest ballast draught, in m, at mid-hold position of all ballast conditions, including ballastwater exchange operation, in the loading manual

Qsw = positive and negative permissible vertical still water shear force for seagoing operation, in kN,at the hull transverse section being considered, as defined in Pt.3 Ch.4 Sec.4 [2.4.2]

Qsw‐p = positive and negative permissible vertical still water shear force for harbour/sheltered wateroperation, in kN, at the hull transverse section being considered, as defined in Pt.3 Ch.4Sec.4 [2.4.3]



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Qsw‐Lcd = vertical still water shear force for the considered loading condition for seagoing operation, inkN, at the hull transverse section considered

Qsw‐Lcd‐p = vertical still water shear force for the considered loading condition for harbour/shelteredwater operation, in kN, at the hull transverse section considered

Qwv = positive and negative vertical wave shear force in seagoing condition, in kN, at the hulltransverse section being considered, as defined in Pt.3 Ch.4 Sec.4 [3.2]

ρc = density of bulk cargo, in t/m3.

1 Introduction

1.1 IntroductionThese rules apply to ships intended for carriage of various unitized and dry bulk cargo.

1.2 ScopeThis section describes requirements for arrangement and hull strength, including:

— general arrangement design, see [2]— structural design principles, see [3]— loads, see [4]— hull girder strength, see [5]— hull local scantling, see [6]— finite element analysis, see [7]— buckling, see [8]— fatigue, see [9].

1.3 Application

1.3.1 The rules given in this section apply to ships arranged for general cargo handling and intended forcarriage of general unitized cargoes and occasional carriage of dry cargoes in bulk.

1.3.2 Ships complying with the requirements given in this section will be assigned one of the ship typenotations General dry cargo ship or Multi-purpose dry cargo ship.

2 General arrangement design

2.1 GeneralThe requirements given in Sec.2 shall be complied with, where applicable.

2.2 Occasional carriage of dry cargoes in bulkThe requirements as follows apply to ship intended for occasional carriage of dry cargoes in bulk:

— the freeboard assigned shall be type B without reduced freeboard— for ships having a freeboard length LLL of not less than 100m, a double side structure complying withSec.2 [2.1.1] shall be arranged.



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3.1 GeneralThe requirements give in Sec.2 shall be complied with, where applicable.

4 Loads

4.1 Standard design loading conditions4.1.1 GeneralThe standard design loading conditions given in the following subsections shall be considered in addition tothe standard loading conditions given in Pt.3 Ch.4 Sec.8 [1].

4.1.2 Dry bulk cargo loading conditionFor ships intended for occasional carriage of dry cargoes in bulk, homogeneous cargo loaded conditionshall be included in the loading manual where the cargo density corresponds to all cargo holds, includinghatchways, being 100% full at scantling draught.

4.1.3 Alternate dry bulk cargo loading conditionIf the ship shall be strengthened for alternate dry bulk cargo loading, alternate loading condition shall beincluded in the loading manual with maximum cargo density at scantling draught.

4.1.4 Container loading conditionFor ships with container transporting capabilities on deck and/or in holds, homogeneous container loadingcondition shall be included in the loading manual at scantling draught.

4.1.5 Block loading conditionIf the ship shall be strengthened for block loading, block loading conditions shall be included in the loadingmanual.A block loading plan shall be submitted, specifying, where applicable, extent and magnitude of maximumblock cargo hold mass on inner bottom, MIB, maximum block cargo mass on weather deck hatch covers,MDeck, and maximum block cargo mass on tween deck hatch covers, MtweenDk, including static pressure due todistributed loads.

Guidance note:The following will be included in the appendix to the classification certificate, where applicable:

— extent and magnitude of maximum block cargo mass, in t, on inner bottom, weather deck hatch covers and tween deck hatchcovers

— static distributed loads, in t/m2, on inner bottom, weather deck hatch covers and tween deck hatch covers.


4.1.6 Heavy lifting operations in harbour/sheltered waterIf the ship shall be equipped with cranes intended for heavy lifting operations in harbour/sheltered water,heavy lifting loading conditions shall be included in the loading manual. The loading conditions shall representcrane operations giving the most unfavourable longitudinal strength results of vertical bending moments,vertical shear forces and torsional moments.



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4.2 Loading conditions for primary supporting members4.2.1 GeneralThe loading conditions for direct strength analysis of primary supporting members shall cover all loadingconditions included in the loading manual, as required in Pt.3 Ch.4 Sec.8 [2] and [4.1].



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4.2.2 Dry cargoes in bulkFor ships intended for occasional carriage of dry cargoes in bulk, design load combinations with dry bulkcargo loads shall be considered.

Guidance note:Ships with L ≥ 150 m and minimum five cargo holds will be assigned a HC notation with standard FE design load combinationsgiven in Pt.6 Ch.1 Sec.4 [4.2.8] for ballast loading conditions and dry bulk cargo loading conditions.For ships not assigned any HC notation, the standard FE design load combinations given in Pt.6 Ch.1 Sec.4 [4.2.8] for HC(M)ships may be used as guidance for ballast loading conditions and dry bulk cargo loading conditions.


4.2.3 Containers on deck and/or in holdsFor ships intended for the carriage of containers in deck and/or in holds, the primary supporting membersshall be strengthened with respect to container loading.For ships having a length L of not less than 150 m, with container transporting capabilities on deck and/orin holds, a homogeneous container load combination at scantling draught and with permissible still waterhogging bending moment in seagoing condition will be required on a case-by-case basis.

Guidance note:FE design load combination LC1 for container ships given in Ch.2 Sec.6 Table 1 may be used as guidance for the dynamic loadcases.


4.2.4 Required loading pattern for ships having a long centre cargo holdFor ships having a long centre cargo hold, and typically equipped with a short hold in fore area and/or aftarea, maximum deflection of ship’s double-side and strengthening with respect to block loading needs shallbe specially considered. Such ships may also be geared with cranes located in way of the ship’s double-sideintended for heavy lifting operations with significant crane reactions that shall be assessed.The following seagoing loading patterns shall in general be considered, see also Table 1:

a) cargo hold carrying MIB with Pdl-s distributed at mid-length position, with no deck load, with all waterballast and fuel oil tanks in way of the cargo hold being empty, at scantling draught TSC

b) cargo hold carrying MIB with Pdl-s distributed at aft-length and fore-length position, with no deck load,with all water ballast and fuel oil tanks in way of the cargo hold being empty, at scantling draught TSC

c) deck carrying 0.8MDeck with PC distributed at mid-length position, with cargo hold carrying MIB - 0.8MDeckwith tank top pressures distributed with the same longitudinal extent as on deck, with all water ballastand fuel oil tanks in way of the cargo hold being empty, at scantling draught TSC

d) deck carrying 0.8MDeck with PC distributed at aft-length and fore-length position, with cargo hold carryingMIB - 0.8MDeck with tank top pressures distributed with the same longitudinal extent as on deck, with allwater ballast and fuel oil tanks in way of the cargo hold being empty, at scantling draught TSC

e) cargo hold carrying MH, with no deck load, with all water ballast and fuel oil tanks in way of the cargohold being empty, at scantling draught TSC

f) cargo hold carrying 0.5MIB with tank top pressures applied to the whole inner bottom, with tween deckat highest position carrying MtweenDk with Pdl-s distributed at mid-length position, with all water ballastand fuel oil tanks in way of the cargo hold being empty, at scantling draught TSC

g) empty cargo hold, with no deck load, with all water ballast and fuel oil tanks in way of the cargo holdbeing 100% full, at the deepest ballast draught TB.

The following additional harbour loading patterns shall be considered, see also Table 1:

h) cargo hold carrying MIB with Pdl-s distributed at mid-length position, with no deck load, with all water

ballast and fuel oil tanks in way of the cargo hold being empty, at scantling draught TSC



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i) cargo hold carrying MIB with Pdl-s distributed at aft-length and fore-length position, with no deck load,with all water ballast and fuel oil tanks in way of the cargo hold being empty, at scantling draught TSC

If the ship is geared with cranes located in way of the ship’s double-side and intended for heavy liftingoperations with SWL not less than 150 t per crane, the following additional loading patterns apply, seealso Table 1:

j) cranes carrying SWL at maximum outboard outreach, with cargo hold being empty, with all anti heeling

tanks at one side being 100% full, at 75% of scantling draughtk) cranes carrying SWL at maximum inboard outreach, with cargo hold being empty, with all double bottom

water ballast tanks in way of the cargo hold being 100% full, at 75% of scantling draughtl) cranes carrying SWL at maximum outboard outreach, with cargo hold carrying 0.8MIB with Pdl-s

distributed at aft-length and fore-length position, with all anti heeling tanks at one side being 100% full,at scantling draught TSC

m) cranes carrying SWL at maximum inboard outreach, with cargo hold carrying 0.8MIB with Pdl-s distributedat aft-length and fore-length position, with all water ballast and fuel oil tanks in way of the cargo holdbeing empty, at scantling draught TSC

n) cranes carrying SWL at maximum outboard outreach, with cargo hold carrying 0.8MIB with Pdl-sdistributed at mid-length position, with all anti heeling tanks at one side being 100% full, at scantlingdraught TSC

o) cranes carrying SWL at maximum inboard outreach, with cargo hold carrying 0.8MIB with Pdl-s distributedat mid-length position, with all water ballast and fuel oil tanks in way of the cargo hold being empty, atscantling draught TSC.

4.2.5 Standard FE design load combinations for cargo hold analysis of a long centre cargo holdIn Table 1 standard design load combinations for cargo hold FE analysis of a long centre cargo hold areshown.

Guidance note:Further explanations of the columns in Table 1 are given in DNV-CG-0127 Sec.3 [4.4].


The design load combinations in Table 1 are representing block loading patterns, homogenous bulk loadingpattern, crane loading patterns, and ballast loading pattern given in the loading manual in accordance with[4.2.4]. If the ship has a length L of not less than 150 m, with container transporting capabilities on deckand/or in holds, additional design load combination in accordance with [4.2.3] may be required on a case-by-case basis.If the loading manual is representing more decisive loading patterns than what is covered in [4.2.4],additional design load combinations will be required on a case-by-case basis.In Table 1 only loading patterns in way of the long centre cargo hold are shown. If the ship is equipped witha short hold in fore area and/or aft area adjacent to the long centre cargo hold that will be included in the FEmodel, the following applies in general:

a) For loading patterns representing homogeneous loading conditions(e.g. homogeneous dry bulk cargoloading, ballast condition and container loading), the same loading patterns shall be applied the shorthold in fore area and/or aft area as for the long centre cargo hold.

b) For loading patterns representing block loading conditions, loading patterns shall be applied to the shorthold in fore area and/or aft area giving the most unfavourable strength results of the double bottom inway of the long centre cargo hold. E.g. when the centre cargo hold has no block loading adjacent to thetransverse bulkheads the adjacent holds shall have maximum loading, and when the centre cargo holdhas block loading adjacent to the traverse bulkheads the adjacent holds shall be empty.

c) For loading patterns representing crane lifting operations at partial draught with cranes outboard (withall cargo holds being empty and no deck load), all anti heeling tanks on one side shall be full.



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d) For loading patterns representing crane lifting operations at partial draught with cranes inboard (with allcargo holds being empty and no deck load), all double bottom ballast tanks in way of the short hold infore area and/or aft area shall be full.

e) For loading patterns representing crane lifting operations at scantling draught, loading patterns shall beapplied to the short hold in fore area and/or aft area giving the most unfavourable strength results of thedouble bottom in way of the long centre cargo hold, see b). The same water ballast tank fillings shall beapplied in way of the short hold in fore area and/or aft area as for in way of the long centre cargo hold.



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Rules for classification: S

hips — DNV-RU-SHIP Pt.5 C

h.1. Edition July 2021

Bulk carriers and dry cargo ships

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Table 1 Standard FE design load combinations for cargo hold analysis of dry cargo ships with a long centre hold

No. Description Loading pattern Aft Mid Fore Weights and tank content Draught% ofperm.SWBM

% ofperm.SWSF

Dynamicloadcase

Seagoing conditions

100% 1)

MaxSFLC

HSM-1FSM-1

100% 2)

MaxSFLC

HSM-1FSM-1

1block loadingmid [4.2.4]item a)

on deck:empty

on inner bottom:

MIB at mid-length with Pdl-sall ballast and FO tanks empty

TSC100%(sag.)

≤100% BSP-1P/S

100% 1)

MaxSFLC

HSM-2FSM-2

100% 2)

MaxSFLC

HSM-2FSM-2

2

block loadingaft and

fore [4.2.4]item b)

on deck:empty

on inner bottom:

MIB at aft and fore with Pdl-sall ballast and FO tanks empty

TSC100%(hog.)

≤100% BSP-1P/S

3heavy deckloads mid

[4.2.4] item c)

on deck:0.8MDeck at mid-length with PCon inner bottom:

MIB-0.8MDeck with same extentas PCall ballast and FO tanks empty

TSC100%(sag.) ≤100%

HSM-1FSM-1

BSP-1P/S

BSR-1P/S

4

heavy deckloads aft andfore [4.2.4]item d)

on deck:0.8MDeck aft and fore with PCon inner bottom:

MIB-0.8MDeck with same extentas PCall ballast and FO tanks empty

TSC100%(hog.) ≤100%

HSM-2FSM-2

BSP-1P/S

BSR-1P/S






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% ofperm.SWSF

Dynamicloadcase

5

homogenousdry bulk

cargo loading[4.2.4]item e)

on deck:empty

in cargo hold:

MH with ρc=1.0

all ballast and FO tanks empty

TSC75%(hog.) ≤100%

HSM-2FSM-2

BSP-1P/S

6heavy tweendeck loading[4.2.4] item f)

on tweendeck at highestposition:MtweenkDk at mid-length with Pdl-sin cargo hold:

0.5MIB applied to whole IB

all ballast and FO tanks empty

TSC75%(hog.) ≤100%

HSM-2FSM-2

BSP-1P/S

7deepest

ballast [4.2.4]item g)

on deck:empty

in cargo hold:

empty

all ballast and FO tanks full

TB75%(hog.) ≤100%

HSM-2FSM-2

BSP-1P/S

Harbour conditions

8block loadingmid [4.2.4]item h)

on deck:empty

on inner bottom:

MIB at mid-length with Pdl-sall ballast and FO tanks empty

TSC100%(sag.) ≤100% N/A

9block loadingaft and fore[4.2.4] item i)

on deck:empty

on inner bottom:

MIB at aft and fore with Pdl-sall ballast and FO tanks empty

TSC100%(hog.) ≤100% N/A






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% ofperm.SWSF

Dynamicloadcase

10 3)crane

outboard onpartial draught[4.2.4] item j)

on deck:maximum crane moment andforce

on inner bottom:

empty

all anti heeling tanks at one sidefull, all other tanks empty

0.75TSC100%(hog.) ≤100% N/A

11 3)

crane inboardon partialdraught[4.2.4]item k)


on inner bottom:

empty

all DB ballast tanks full, all othertanks empty

0.75TSC100%(hog.) ≤100% N/A

12 3)crane

outboard withMsw-p-h[4.2.4]

item l)


on inner bottom:

0.8MIB at aft and fore with Pdl-sall anti heeling tanks at one sidefull, all other tanks empty

TSC100%(hog.) ≤100% N/A

13 3)crane inboardwith Msw-p-h[4.2.4]item m)


on inner bottom:

0.8MIB at aft and fore with Pdl-sall ballast and FO tanks empty

TSC100%(hog.) ≤100% N/A






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% ofperm.SWSF

Dynamicloadcase

14 3)crane

outboard withMsw-p-s[4.2.4]item n)


on inner bottom:

0.8MIB at mid-length with Pdl-sall anti heeling tanks at one sidefull, all other tanks empty

TSC100%(sag.) ≤100% N/A

15 3)crane inboardwith Msw-p-s[4.2.4]item

o)


on inner bottom:

0.8MIB at mid-length with Pdl-sall ballast and FO tanks empty

TSC100%(sag.) ≤100% N/A

1) The shear force shall be adjusted to target value at x < 0.5 L.2) The shear force shall be adjusted to target value at x > 0.5 L.3) Applicable for cranes with SWL ≥ 150 t only.


4.2.6 Loading patterns for ships with two, three or four cargo holdsThe design of the vessels shall be based on the design loading conditions included in the loading manual. Thestandard design loading conditions are given in [4.1].For the cargo holds where the dry cargoes are designed for loading in blocks in one cargo hold, the loadingpatterns according to [4.2.4] shall be considered.For the cargo holds where the dry cargoes are not designed for loading in blocks in one cargo hold, theloading patterns shall follow the principle according to Pt.6 Ch.1 Sec.4, taking maximum upward ordownward net loads on the double bottom into consideration.

Guidance note:For the cargo holds where the dry cargoes are not designed for loading in blocks in one cargo hold, the hold mass curves should beprepared accordingly, e.g., according to HC(M) notation.


5 Hull girder strength

5.1 Vertical hull girder bending strength5.1.1 GeneralThe hull girder bending strength assessment shall in general be carried out in accordance with Pt.3 Ch.5Sec.2 [1].For harbour/sheltered water operation, the permissible still water bending moment criteria given in [5.1.2]shall be complied with, applying a wave correction factor for permissible vertical still water bending moment,fhar-M, differing from Pt.3 Ch.5 Sec.2.

5.1.2 Design criteria for harbour/sheltered water operationThe permissible hull girder bending moment, in kN/m, for harbour/sheltered water operation in hogging andsagging shall comply with the following criteria:

The bending moment Mwv used above shall have the same sign as the considered bending moment Msw-p.

5.2 Vertical hull girder shear strength5.2.1 GeneralThe hull girder shear strength assessment shall be carried out in accordance with Pt.3 Ch.5 Sec.2 [2]applying shear force correction given in [5.2.4]. Within the cargo hold region, shear force correction shall beapplied to each loading condition given in the loading manual, and the loading/unloading sequences, whereapplicable.For ships having less than five cargo holds, the requirements for shear force correction given in [5.2.4] maybe disregarded.For harbour/sheltered water operation, the permissible still water shear force criteria given in [5.2.3] shallbe complied with, applying a wave correction factor for permissible vertical still water shear force, fhar-Q,differing from Pt.3 Ch.5 Sec.2.

5.2.2 Design criteria for seagoing operationThe positive and negative permissible vertical still water shear force, in kN, for seagoing operation shallcomply with the following criteria:

The shear force Qwv used above shall have the same sign as the considered shear force Qsw.



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The vertical still water shear forces, in kN, for all loading conditions for seagoing operation, shall comply withthe following criteria:

where:

ΔQmdf = shear force correction, in kN, as defined in [5.2.4], for seagoing operation.

The shear force Qsw used above shall have the same sign as the considered shear force Qsw-Lcd.

5.2.3 Design criteria for harbour/sheltered water operationThe positive and negative permissible vertical still water shear force, in kN, for harbour/sheltered wateroperation shall comply with the following criteria:

The shear force Qwv used above shall have the same sign as the considered shear force Qsw-p.

The vertical still water shear forces, in kN, for all loading conditions for harbour/sheltered water operation,shall comply with the following criteria:

where:

ΔQmdf = shear force correction, in kN, as defined in [5.2.4], for harbour/sheltered water operation.

The shear force Qsw-p used above shall have the same sign as the considered shear force Qsw-Lcd-p.

5.2.4 Shear force correctionShear force correction, which takes into account the portion of loads transmitted by the double bottomlongitudinal girders to the transverse bulkheads, shall be considered.

For the considered cargo hold, the shear force correction at the considered transverse section shall beobtained, in kN, from the following formula:

where:

Cd = distribution coefficient:

— Cd = -1 at the aft end of the considered cargo hold— Cd = 1 at the fore end of the considered cargo hold— Cd = linearly distributed inside the considered cargo hold— Cd = 0 at the fore bulkhead of the foremost cargo hold, at the aft bulkhead of the aftmostcargo hold and in the middle of the foremost and the aftmost cargo hold

α = coefficient:



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M = mass, in t, in the hold in way of the considered transverse section for the considered loadingcondition. M shall include the mass of ballast water and fuel oil located directly below the flatportion of the inner bottom, if any, excluding the portion under the bulkhead stool, if any

BH = breadth of the cargo hold, in m, as defined in [2]lH = length of the cargo hold, in m, as defined in [2]l0, b0 = length and breadth, respectively, in m, of the flat portion of the double bottom in way of the hold

considered; b0 shall be measured on the hull transverse section at the middle of the hold

but not greater than 3.7

TLC,mh = draught, in m, measured vertically on the hull transverse section at the middle of the holdconsidered, from the moulded baseline to the waterline in the loading condition considered

ΔQCF = shear force correction for the full holdΔQCE = shear force correction for the empty hold.

Figure 1 Shear force correction, ΔQC

5.3 Loading instrument



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5.3.1 Ships with a long center cargo holdFor ships with a long center cargo hold, information on torsional moments shall be included in the loadinginstrument.

5.3.2 Ships applying shear force correction upon vertical hull girder shear strength assessmentFor ships applying shear force correction upon vertical hull girder shear strength assessment in accordancewith [5.2.4], the loading instrument shall provide hull girder shear strength results, including shear forcecorrection.


6.1 Plating6.1.1 Plating subject to lateral pressureFor ships intended for occasional carriage of dry cargoes in bulk the requirements given in Pt.3 Ch.6 Sec.4[1] shall be complied with, applying the additional design load sets given in Sec.2 [5.1].

6.2 Stiffeners6.2.1 Stiffeners subject to lateral pressureFor ships intended for occasional carriage of dry cargoes in bulk the requirements given in Pt.3 Ch.6 Sec.5[1] shall be complied with, applying the additional design load sets given in Sec.2 [5.1].

6.3 Primary supporting members6.3.1 GeneralFor primary supporting members not assessed in accordance with [7.2], the requirements given in Pt.3 Ch.6Sec.6 [2] shall be complied with, applying the loading conditions for PSM given in [4.2], with the additionaldesign load sets given in Sec.2 [5.1].

6.4 Intersection of stiffeners and primary supporting members6.4.1 Connection of stiffeners to primary supporting membersFor ships intended for occasional carriage of dry cargoes in bulk the requirements for connection of stiffenersto primary supporting members shall comply with Pt.3 Ch.6 Sec.7 [1], including the internal pressure due todry bulk cargo given in Sec.2 [3].

6.5 Fixed cargo securing devices6.5.1 Supporting structures of fixed cargo securing devicesStiffeners and girders supporting fixed cargo securing devices shall comply with the requirements givenin Pt.3 Ch.6 Sec.5 and Pt.3 Ch.6 Sec.6, applying the certified MSL (maximum securing load) with theacceptance criteria AC-II.



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7 Finite element analysis

7.1 GeneralFinite element analysis shall be carried out according to general assumptions, methodology and requirementsfor the finite element analysis given in Pt.3 Ch.7 and according to methods and procedures given in theSociety's document DNV-CG-0127 unless otherwise specified in this section.

Guidance note:Calculation methods acceptable to the Society are further outlined in DNV-CG-0151.


Guidance note:For ships equipped with cranes for heavy lifting operations and with a long centre cargo hold, a global strength analysis may berequired on a case by case basis.


7.2 Cargo hold analysis7.2.1 GeneralCargo hold analysis shall be carried out in accordance with Pt.3 Ch.7 Sec.1 and Pt.3 Ch.7 Sec.3 usingdetailed requirements given in the following subsections.

Guidance note:Ships with L ≥ 150 m and minimum five cargo holds will be assigned a HC notation with additional requirements for cargo holdanalysis given in Pt.6 Ch.1 Sec.4 [7.1] and requirements for local structural strength analysis given in Pt.6 Ch.1 Sec.4 [7.2].


7.2.2 ApplicationCargo hold analysis of midship region is mandatory irrespective of the ship’s length.For ships with a long centre cargo hold, only cargo hold analysis of the long centre hold is mandatory. Cargohold analysis of short holds in fore area and/or aft area, if any, is not mandatory.

7.2.3 Extent of modelFor ships with a long centre cargo hold and not equipped with a short hold in fore area and aft area, therequired longitudinal extent of the model will be considered on a case-by-case basis.

Guidance note:The minimum extent of the model should be from the engine room front bulkhead to the long centre hold front bulkhead. Theevaluation area will then typically be limited to within 75% of the model length.


Guidance note:For evaluation of all structural members within the centre cargo hold, including transverse bulkheads, the following modellingshould be applied:

— if the long centre cargo hold is adjacent to the machinery spaces (with no short hold in the aft area), the typical extension of anaftmost cargo hold model into the machinery spaces outlined in DNV-CG-0127 Finite element analysis, may be used as guidance

— if the long centre cargo hold is adjacent to the fore peak (with no short hold in the fore area), the typical extension of an foremostcargo hold model into the fore peak outlined in DNV-CG-0127 Finite element analysis, may be used as guidance.




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For ships equipped with cranes located in way of the ship’s double-side and intended for heavy liftingoperations, the lower portion of the crane pedestals extending up to the connecting flange to the slewingbearing shall be included in the model.

7.2.4 FE load combinationsThe load combinations to be applied to the FE model shall be based on the required design load combinationsfor direct strength analysis of PSM given in [4.2].

7.2.5 Loads due to dry bulk cargoBulk pressures and shear loads, where applicable, shall be applied to the FE model in accordance with Sec.2[3].

7.2.6 Loads due to block loading on inner bottomWhere applicable, static and dynamic pressure loads due to block cargo mass, MIB in t, acting on the innerbottom shall be applied to the inner bottom as follows:

— in harbour conditions, static pressures, Pdl-z in kN/m2, in vertical direction (positive downward to the

plating), shall be:

— in seagoing conditions, static and dynamic pressures, Pdl-z in kN/m2, in vertical direction (positive

downward to the plating), shall be:

— in seagoing conditions, dynamic shear pressures, Pdl-y in kN/m2, in transverse direction (positive to port),

shall be:

Shear pressures in longitudinal direction may be omitted.

7.2.7 Loads due to block loading on tween deck hatch coversWhere applicable, static and dynamic forces and tipping moments due to block cargo mass, MtweenDk in t,acting on tween deck hatch covers, shall be applied in way of the hatch cover pockets at the relevant stopperlocations. For a typical arrangement with four active stoppers in z direction and two in y direction for eachhatch cover, forces shall be applied as follows:

— in harbour conditions, static forces, Fdl-z in kN, in vertical direction (positive downward on both sides),shall be:

— in seagoing conditions, static and dynamic forces, Fdl-z in kN, in vertical direction (positive downward onboth sides), shall be:

— in seagoing conditions, dynamic forces, Fdl-y in kN, in transverse direction (for BSR-1P and BSP-1P on portside only and positive to port), shall be:

Forces in longitudinal direction may be omitted.



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7.2.8 Loads due to block loading on weather deck hatch coversWhere applicable, static and dynamic forces and tipping moments due to block cargo mass, MDeck in t, actingon weather deck hatch covers, shall be applied at the relevant stopper locations. For typical arrangementwith four active stoppers in z direction and one in y direction for each hatch cover, forces shall be applied asfollows:

— in harbour conditions, static forces, FC-z in kN, in vertical direction (positive downward on both sides),shall be:

— in seagoing conditions, static and dynamic force FC-z in kN, in vertical direction (positive downward onboth sides), shall be:

— in seagoing conditions, dynamic force, FC-y in kN, in transverse direction (typically on the side where shipcranes are arranged), shall be:

Forces in longitudinal direction can be omitted.

7.2.9 Crane loadsIf the ship is equipped with cranes located in way of the ship’s double-side and intended for heavy liftingoperations, forces and bending moments shall be applied to the crane pedestals in accordance with Pt.3Ch.11 Sec.2 [4]. A dynamic factor, ψ, specified by the designer and being less than given in Pt.3 Ch.11 Sec.2[4.5.1] will be considered on a case-by-case basis.

7.2.10 Container loadsContainer loads, where applicable, shall be applied to the FE model in accordance with DNV-CG-0131 Sec.2[1.3.3].

7.3 Global strength analysisGeneral dry cargo ships and multi-purpose dry cargo ships may, upon request, be investigated by anextended strength analysis with a global FE-model. Such ships may be assigned the additional class notationRSD, see Pt.6 Ch.1 Sec.8.

Guidance note:Particular for ships equipped with cranes for heavy lifting operations and/or with a long centre cargo hold such a global strengthanalysis is valuable, see DNV-CG-0151 Sec.1 [2].


7.4 Embedded cargo hold analysis7.4.1 GeneralThe cargo hold FEA according to [7.2] may be carried out with the global FE-model, when the mesh size inmid ship area corresponds with the stiffener spacing as described in DNV-CG-0127 Sec.3 [2.2.4].

7.4.2 Direct wave analysisBased on the load procedure described in DNV-CG-0131 Sec.2 [1], the required load combinations given in[4.2] shall be generated by direct wave analysis for a 10-8 probability level of exceedance.



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Inside of the investigated cargo hold the loading patterns shall be in alignment with [4.2.5]. Outside of thishold the loading patterns can be adjusted in such a way, that the required draught and still water bendingmoment can be fulfilled on an even trim.

8 Buckling

8.1 Hull girder bucklingFor ships intended for occasional carriage of dry cargoes in bulk, the requirements given in Pt.3 Ch.8 Sec.3shall be complied with, applying the additional design load sets given in Sec.2 [5.1].

9 Fatigue

9.1 General

9.1.1 Fatigue assessment shall be carried out for ships having a length L of not less than 90 m in accordancewith Pt.3 Ch.9, using detailed requirements in the following subsections.

Guidance note:Calculation methods acceptable to the Society are further outlined in DNV-CG-0129 Fatigue assessment of ship structure.


9.2 Prescriptive fatigue strength assessmentWithin the cargo region, the following details shall be considered in accordance with DNV-CG-0129 Fatigueassessment of ship structure:

— end connections of longitudinal stiffeners to transverse web frames and transverse bulkheads shall fulfillrelevant requirements of DNV-CG-0129 Sec.4

— other welded details, e.g. transverse butt welds, hatch cover resting pads, equipment holders etc. in theupper part of the hull girder shall fulfill relevant requirements of DNV-CG-0129 Sec.3 [5]

— knuckles and discontinuities of longitudinal structural members, e.g. hatch coamings, in the upper part ofthe hull girder, according to DNV-CG-0129 Sec.3 [5].



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SECTION 6 BULK CARRIERSSymbolsFor symbols not defined in this section, see Pt.3 Ch.1 Sec.4 [2].

1 Introduction

1.1 IntroductionThese rules apply to ships primarily intended for the carriage of solid bulk cargoes.

1.2 ScopeThis section describes requirements for arrangement and hull strength.

1.3 Application

1.3.1 This section is applicable to ships primarily intended to carry dry cargo in bulk, excluding those shipsassigned the ship type class notation Ore carrier.

1.3.2 These rules are applicable to sea-going single deck ships with cargo holds of single and or double sideskin construction, with a double bottom, hopper side tanks and top-wing tanks fitted below the upper deck.Typical cargo hold cross-sections with hopper side tanks and top-wing tanks are given in Figure 1.

Figure 1 Typical hold cross-sections a) single side skin bulk carrier b) double side skin bulk carrier

1.3.3 These rules are also applicable to ships primarily intended for the carriage of solid bulk cargoes withother arrangements than shown in Figure 1.

1.3.4 Ships complying with the requirements given in this section will be assigned the ship type classnotation Bulk carrier.



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2 CSR and non-CSR bulk carriers

2.1 CSR Bulk carriers

2.1.1 Bulk carriers having a length L of 90 m and above and having at least one cargo hold with cross-sections as given in Figure 1 , in accordance with CSR Pt.1 Ch.1 Sec.1 [1.2], will be assigned with CSRnotation, and shall comply with CSR Pt.1 and CSR Pt.2 Ch.1, in addition to requirements as below.Applicable requirements of Pt.3 are listed in Pt.3 Ch.1 Sec.1 [1.1.2].The following requirements given in Ch.1 are applicable:

— Sec.1— Sec.2 [8].

2.1.2 For regions of the structure for which CSR Pt.1 and CSR Pt.2 Ch.1 do not apply, the appropriateclassification rules shall be applied.In cases where CSR Pt.1 and CSR Pt.2 Ch.1 do not address certain aspects of the ship's design, theapplicable classification rules shall be applied.

2.1.3 Equivalency to the rules of alternative methods used for the design and the determination of scantlings shallbe assessed following IACS Rec.165.

2.2 Non-CSR Bulk carriers

2.2.1 Ships other than CSR bulk carriers as given in [2.1.1], shall comply with following requirements:

— Sec.2

— Sec.5, including those for ships intended for occasional carriage of dry cargoes in bulk, excluding Sec.5[2.2].



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SECTION 7 ORE CARRIERSSymbols


fhar = wave correction factor for harbour/sheltered water operation, as defined in Pt.3 Ch.5 Sec.2Msw‐p = permissible vertical still water bending moment for harbour/sheltered water operation, in

kN, for hogging and sagging respectively at the hull transverse section being considered, asdefined in Pt.3 Ch.4 Sec.4 [2.2.3]

Qwv‐LC = vertical wave shear force for seagoing operation, in kN, at the hull transverse sectionconsidered for the considered dynamic load case, as defined in Pt.3 Ch.4 Sec.4 [3.5.3]

Qsw = positive and negative permissible vertical still water shear force for seagoing operation, in kN,at the hull transverse section being considered, as defined in Pt.3 Ch.4 Sec.4 [2.4.2]

Qsw‐p = positive and negative permissible vertical still water shear force for harbour/sheltered wateroperation, in kN, at the hull transverse section being considered, as defined in Pt.3 Ch.4Sec.4 [2.4.3]

Qwv = positive and negative vertical wave shear force for seagoing operation, in kN, at the hulltransverse section being considered, as defined in Pt.3 Ch.4 Sec.4 [3.2].

1 Introduction

1.1 IntroductionThese rules apply to ships primarily intended for the carriage of ore cargoes.



1.3 Application

1.3.1 These rules are applicable to vessels with the following characteristics:

— primarily intended to carry ore cargoes in dry bulk with density up to 3 t/m3, e.g. iron ore— sea-going single deck ships having two longitudinal bulkheads and a double bottom throughout the cargoregion

— intended for carrying ore cargoes in the centre holds only, as indicated in Figure 1.



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Figure 1 Typical midship section of ore carrier

1.3.2 Ships complying with the requirements given in this section will be assigned the ship type classnotation Ore carrier.





3.2 Structural arrangement - fore peak structure3.2.1 Arrangement of floorsWhere transverse stiffening is applied, floors shall be fitted at each web frame location.Where longitudinal stiffening is applied, the spacing of floors shall not be greater than 4.5 m or fivetransverse frame spacings, whichever is smaller.The depth of the floors shall not be less than the height of the double bottom in the foremost cargo hold andthe upper edge shall be stiffened.

3.2.2 Arrangement of bottom girdersThe fore peak shall be fitted with a centreline girder and side girders. The transition (scarfing) of thelongitudinal bulkhead shall be connected to a side girder.Where transverse stiffening is applied, the spacing of bottom girders shall not exceed 2.5 m.Where longitudinal stiffening is applied, the spacing of bottom girders shall not exceed 3.5 m.The depth of the bottom girders shall not be less than the height of the double bottom in the foremost cargohold and the upper edge shall be stiffened.



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3.2.3 Centreline bulkheadAlternatively to the requirements for longitudinal girders given in [3.2.2] a perforated centreline bulkheadmay be fitted supporting all floors in the fore peak, and extending not less than two platform decks/stringerlevels above the inner bottom.

3.2.4 Arrangement of side web framesThe spacing of side web frames in the fore peak shall not be greater than 4.5 m or five transverse framespacings, whichever is smaller.

3.2.5 Support of chain lockerEach chain locker shall be supported by the ship's side or the fore peak bulkhead by minimum one partialbulkhead connecting to the chain locker wall.Alternatively, it shall be demonstrated that the structures supporting the chain locker have sufficient strengthby means of a partial ship model including the chain locker. In this analysis, the mass of the chain cableas uniform distributed load on the bottom of the chain locker shall be considered in combination with EDWHSA-1 and acceptance criteria AC-II. Other means of strength verification may be agreed with the Societyand accepted on a case-by-case basis.

3.3 Structural arrangement - machinery space3.3.1 Arrangement of side girdersThe spacing of side web frames in the engine room shall not be greater than 4.5 m or five transverse framespacings, whichever is smaller.Web frames shall be connected at the top and bottom to members of suitable stiffness, and supported bydeck transverses.

3.3.2 Support of heavy fuel oil tanksPartial end bulkheads forming the boundary of heavy fuel oil storage tanks shall extend down to the outershell with vertical stiffening.

3.3.3 Termination of longitudinal bulkheadThe longitudinal bulkhead shall continue inside the machinery space for a distance not less than 4.5 m or fivetransverse frame spacings, whichever is greater, before starting the tapering of the bulkhead structure, e.g.scarfing brackets.The longitudinal bulkhead inside the machinery space shall have the same hull girder shear strength, i.e.same net plate thickness and yield strength, as that required immediately in front of the engine roombulkhead according to [5.1].

4 Loads

4.1 Standard design loading conditions4.1.1 GeneralThe standard design loading conditions given in [4.1.2] shall be considered in addition to the standardloading conditions given in Pt.3 Ch.4 Sec.8 [1].

4.1.2 Ore cargo loading conditionHomogeneous cargo loading condition shall be included in the loading manual where the cargo density isequal to 3.0 t/m3 in all cargo holds at scantling draught.



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4.2 Loading conditions for primary supporting members4.2.1 GeneralThe loading conditions for direct strength analysis of primary supporting members shall envelope all loadingconditions included in the loading manual, as required in Pt.3 Ch.4 Sec.8 [2] and [4.1].

Guidance note:Ore carriers with L ≥ 150 m will be assigned an OC notation with standard FE design load combinations given in Pt.6 Ch.1 Sec.5[4.2.8] for ballast and cargo loading conditions, and loading/unloading sequences.



5.1 Vertical hull girder shear strength5.1.1 GeneralThe hull girder shear strength assessment shall in general be carried out in accordance with Pt.3 Ch.5 Sec.2[2].Within the cargo hold region, the shear force correction shall be accounted for when establishing the totalhull girder shear force capacity in accordance with [5.1.2].

5.1.2 Total hull girder shear capacityThe total vertical hull girder shear capacity, in kN, is the minimum of the calculated values for all platesi contributing to the hull girder shear of the considered transverse section and shall be obtained by thefollowing formula:

where:

qvi‐gr = unit shear flow, in mm-1, for the plate i based on gross thickness, as defined in Pt.3 Ch.5 Sec.2ti‐gr = gross thickness, in mm, for plate i. For side or longitudinal bulkheads within the cargo hold

region, ti-gr shall be equal to tsfi-grτi‐perm = permissible shear stress, in N/mm2, for plate i, shall be:

For side or longitudinal bulkhead the gross thickness of the plating above the inner bottom level, tsfi-gr forplate i, in mm, is given by:

where:

tΔi = thickness deduction for plate i, in mmtΔi1 for sidetΔi2 for longitudinal bulkhead.



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For side, the vertical distribution of thickness reduction for shear force correction shall be linear as indicatedin Figure 2. The thickness deduction, tΔi1 in mm, to account for shear force correction on the plate i, shall be:

For longitudinal bulkhead, the vertical distribution of thickness reduction for shear force correction shall betriangular as indicated in Figure 3. The thickness deduction, tΔi2 in mm, to account for shear force correctionon the plate i, shall be:

where:

δQ3 = shear force correction for side or longitudinal bulkhead as defined in [5.1.3], in kNℓh = length of the cargo hold between mid-depth of the corrugated bulkhead(s), in mhblk = height of longitudinal bulkhead, in m, defined as the distance from inner bottom to the deck at the

top of the bulkhead, as shown in Figure 2 and Figure 3xblk = minimum longitudinal distance from section considered to the nearest cargo hold transverse

bulkhead, in m. Shall be positive and not greater than 0.5ℓhzp = vertical distance from the lower edge of plate i to the base line, in m, but not less than hdbhdb = height of double bottom, in m, as shown in Figure 2 and Figure 3.

Figure 2 Shear force correction for side



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Figure 3 Shear force correction for longitudinal bulkheads

5.1.3 Shear force correctionThe shear force correction, δQ3, in kN, shall be obtained from the following formula:

where:

Fdb = maximum resulting force on the double bottom in a cargo hold, in kN, as defined in [5.1.4]

K3 = correction factor, shall be equal to:K31 for sideK32 for longitudinal bulkhead.

The shear force correction factor, K3, may be based on a direct strength analysis.

Guidance note:A midship FE cargo hold model applying a static condition with MH in way of mid-hold only on TSC may be used for obtaining r andCT.r should be obtained by taking the ratio in shear force between the side shell and the longitudinal bulkhead in way of thetransverse bulkhead.CT should be obtained by taking the ratio in shear force between the longitudinal girders in way of lower stools and total shearforce acting on the double bottom.




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where:

CT = fraction of the centre hold load going through longitudinal girders directly to the transversebulkhead found by a direct calculation. A value of nL/(nL+nB) may otherwise be used

lh = as given in [5.1.2]ltk = length between transverse bulkheads in wing space aligned with cargo hold transverse

bulkheads, in ms = distance between floors in the cargo hold, in mnL = number of continuous longitudinal girders in the cargo holdnB = number of floors in the cargo hold

r = ratio between the part of load in cargo hold carried by transverse wash/watertightbulkhead, if any, and transverse primary supporting members from longitudinal bulkheadto side, and the part remaining in the longitudinal bulkhead:

b = mean span of transverse primary supporting members in the wing space, includingbrackets, in m

AT‐gr = gross shear area of the transverse wash/watertight bulkhead corresponding to definitionfor ns, in the wing space, in cm

2, taken as the smallest area in a vertical sectionA1‐gr, A2‐gr = gross areas, as defined in Table 1, in m2

f31 = shear force distribution factor, as defined in Table 1 or based on a numerical shear flowcalculation taken as the fraction of the hull girder shear force carried by one side, includingthe vertical projection of bilge plating

f32 = shear force distribution factor, as defined in Table 1 or based on a numerical shear flowcalculation taken as the fraction of the hull girder shear force carried by one longitudinalbulkhead, including the margin girder under the inner bottom

n = number of transverse web frames in the wing space along length of cargo hold lh.nS = number of transverse wash/watertight bulkheads in the wing space along length of cargo

hold lh, in between the cargo hold transverse bulkheads

R = total efficiency of the transverse primary supporting members in the wing space in cm2

AQ‐gr = gross shear area, in cm2, of a transverse web frame in the wing space, taken as the sumof the gross shear areas of bottom transverse web , cross tie(s) and deck transverse web.The gross shear area shall be calculated at the mid span of the members

Ipsm‐gr = gross moment of inertia for a transverse web frame, in cm4, in the wing space, takenas the sum of the moments of inertia of bottom transverse web, cross tie(s) and decktransverse web. The gross moment of inertia shall be calculated at the mid span of themember including an attached plate width equal to the primary supporting memberspacing.



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Table 1 Shear force distribution factor for ore carrier

Hull configuration f3 factor

where:A1‐gr, A2‐gr = net projected area onto the vertical plane based on gross thickness, tgr, of the side shell or the

longitudinal bulkhead respectively, at one side of the section under consideration.

The area A1-gr includes the gross plating area of the side shell, including the bilge.

The area A2-gr includes the gross plating area of the longitudinal bulkhead, including the outboardgirder under the inner bottom.

5.1.4 Maximum resulting force on double bottomThe maximum vertical resulting force on the double bottom in a cargo hold, Fdb, in kN, shall be the greaterof:

— max downwards net vertical force, applicable for the longitudinal bulkhead:

— max upwards vertical force, applicable for the side and the longitudinal bulkhead:

where:

b2 = mean breadth of the cargo hold at inner bottom level, in mlh = as given in [5.1.2]Tmean = draught at the mid-length of the hold for the loading condition considered given in Table 2.



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Table 2 Tmean values depending on allowable loading defined by the hold mass curves

Tmean1)

Structural configuration Downwards/upwards force, FdbOC(H) ships OC(M) ships In general

max downwards net vertical force, Fdb+

TSC TS,MIN,ALT,SEA TSCfor seagoing operation

max upwards net vertical force, Fdb- THB TS,MAX,ALT,SEA THB

max downwards net vertical force, Fdb+

TS,MIN,FULL,HARfor harbour/shelteredwater operation

max upwards net vertical force, Fdb- TS,MAX,EMPTY,HAR

NA

1) For OC(M) and OC(H) ships Tmean shall be based on the knuckle points of the hold mass curves for single holdloading, see Pt.6 Ch.1 Sec.5 [5.2] for hold mass curves and Pt.6 Ch.1 Sec.5 [1.5.1] for symbol definitions.

5.1.5 Design criteria for seagoing operationThe positive and negative permissible vertical still water shear force, in kN, for seagoing operation shallcomply with the following criteria:

where:

QR = total vertical hull girder shear capacity, in kN, as defined in [5.1.2], applying shear force correctionin accordance with [5.1.3] in seagoing operation.

The shear force Qwv used above shall have the same sign as the considered shear force Qsw.

5.1.6 Design criteria for harbour/sheltered water operationThe positive and negative permissible vertical still water shear force, in kN, for harbour/sheltered wateroperation shall comply with the following criteria:

The shear force Qwv used above shall have the same sign as the considered shear force Qsw-p.

5.2 Hull girder yield check5.2.1 GeneralOre carriers shall be considered as ships without large deck openings. The requirements given in Pt.3 Ch.5Sec.3 [3] are therefore not mandatory in this regard.

5.2.2 Hull girder shear stressesThe hull girder shear stress requirements given in Pt.3 Ch.5 Sec.3 [2.2] shall be complied with, applyingshear stresses induced by vertical shear forces in accordance with [5.2.3] and [5.2.4].

5.2.3 Definition of hull girder shear stresses induced by vertical still water shear force forseagoing operationThe shear stresses, in N/mm2, induced by vertical still water shear force for seagoing operation at thetransverse section being considered, are obtained from the following formulae:



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where:

qvi‐n50 = unit shear flow, in mm-1, for the plate i based on ti-n50, as defined in Pt.3 Ch.5 Sec.3

ti‐n50 = net thickness of plate i, in mm. For longitudinal bulkheads within the cargo hold region, ti-n50shall be equal to tsfi-n50.

For side or longitudinal bulkhead the net thickness of the plating above the inner bottom level, tsfi-n50 forplate i, in mm, is given by:

where:

tΔi = thickness deduction for plate i, in mm obtained in accordance with [5.1.2], applying shear forcecorrection in accordance with [5.1.3] for seagoing operation.

5.2.4 Definition of hull girder shear stress induced by vertical wave shear forceThe shear stress, in N/mm2, induced by vertical wave shear force for seagoing operation for a dynamic loadcase at the transverse section being considered, is obtained from the following formula:

where:

qvi‐n50 = as given in [5.2.3]ti‐n50 = as given in [5.2.3].



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6.1 Minimum thickness6.1.1 Minimum thickness in fore peakThe minimum net thickness, in mm, of decks and perforated flats acting as transverse strength membersshall not be less than:

t = 0.014b

6.1.2 Minimum thickness in machinery spaceThe minimum net thickness, in mm, of platform decks and strength deck acting as transverse strengthmembers shall not be less than:

t = 0.014b

6.2 Plating6.2.1 Plating subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.4 [1] shall be complied with, applying the additional design loadsets given in Sec.2 [5.1].

6.3 Stiffeners6.3.1 Stiffeners subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.5 [1] shall be complied with, applying the additional design loadsets given in Sec.2 [5.1].

6.3.2 Minimum moment of inertia of stiffeners in fore peakFor stiffened plate panels mentioned in [6.1.1] with longitudinal stiffening orientation, the net moment ofinertia, in cm4, about the neutral axis parallel to the effective attached plate of stiffener shall not be lessthan:

I = 19l4

6.3.3 Minimum moment of inertia of stiffeners in machinery spaceFor stiffened plate panels mentioned in [6.1.2], with longitudinal stiffening orientation, the net moment ofinertia, in cm4, about the neutral axis parallel to the effective attached plate of stiffener shall not be lessthan:

I = 19l4



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6.4.2 Primary supporting members in fore peakScantlings of primary supporting members being part of a complex 3-dimensional structural system, suchas bottom girders, floors, side girders, side stringers, and deck girders, shall be based on an advancedcalculation method in accordance with Pt.3 Ch.6 Sec.6 [2.2].

6.4.3 Primary supporting members in machinery spaceScantlings of primary supporting members being part of a complex 3-dimensional structural system, suchas side girders, side stringers, and deck girders, shall be based on an advanced calculation method inaccordance with Pt.3 Ch.6 Sec.6 [2.2].

6.5 Intersection of stiffeners and primary supporting members6.5.1 Connection of stiffeners to primary supporting membersThe requirements for connection of stiffeners to primary supporting members shall comply with Pt.3 Ch.6Sec.7 [1], including the internal pressure due to dry bulk cargo given in Sec.2 [3].



Guidance note:Calculation methods acceptable to the Society are further outlined in DNV-CG-0127 Finite element analysis.


Guidance note:Ore carriers with L ≥ 150 m will be assigned an OC notation with additional requirements for cargo hold analysis given in Pt.6 Ch.1Sec.5 [7.1] and requirements for local structural strength analysis given in Pt.6 Ch.1 Sec.5 [7.2].


7.1.2 ApplicationCargo hold analysis of midship region is mandatory irrespective of the ship’s length.


7.1.4 Internal loadsBulk pressures and shear loads shall be applied to the FE model in accordance with Sec.2 [3].



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8 Buckling

8.1 Hull girder bucklingThe hull girder buckling requirements given in Pt.3 Ch.8 Sec.3 shall be complied with, applying the additionaldesign load sets given in Sec.2 [5.1]. For hull girder buckling assessment of design load sets representingdesign load scenario 2, hull girder shear stress components in accordance with [5.2.3] and [5.2.4] shall beapplied.

9 Fatigue

9.1 General

9.1.1 Fatigue assessment shall be carried out for ships having a length L of not less than 90 m in accordancewith Pt.3 Ch.9, using detailed requirements in the following subsections.



9.2 Prescriptive fatigue strength assessment9.2.1 GeneralWithin the cargo region, the fatigue life of longitudinal end connections in way of web frames and transversebulkheads shall be assessed in accordance with DNV-CG-0129 Sec.4.



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SECTION 8 SHIPS SPECIALISED FOR THE CARRIAGE OF A SINGLETYPE OF DRY BULK CARGOSymbolsFor symbols not defined in this section, see Pt.3 Ch.1 Sec.4.

1 Introduction

1.1 IntroductionThese rules apply to ships specialised for the carriage of a single type of dry bulk cargo.



1.3 Application

1.3.1 The requirements in this section are applicable to ships intended for the carriage of a single type of drybulk cargo limited to one of the following: woodchips, cement, fly ash or sugar.

1.3.2 Ships complying with the requirements given in this section will be assigned the ship type classnotation X carrier, where X denotes the type of cargo to be carried, e.g. Woodchips, Cement, Fly ash orSugar.


2.1 Compartment arrangement2.1.1 Arrangement of cargo hold regionThe ship shall have a double bottom within the cargo region and a single deck. Hatches to cargo holds shallbe arranged as required for access only, and for the closed loading and unloading arrangement.

2.1.2 Loading and unloading arrangementThe cargo holds shall be arranged with a closed loading and unloading arrangement. Documentation of theintended loading and unloading system shall be submitted for information.



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3.1 Structural arrangementThe requirements given in Sec.2 [2] shall be complied with, as applicable.

4 Loads

4.1 Standard design loading conditions4.1.1 GeneralThe standard design loading conditions given in the following subsections shall be considered in addition tothe standard loading conditions given in Pt.3 Ch.4 Sec.8 [1].

4.1.2 Dry bulk cargo loading conditionHomogeneous cargo loaded condition shall be included in the loading manual where the cargo densitycorresponds to all cargo holds, including hatchways, being 100% full at scantling draught.

4.1.3 Guidance for loading/unloading sequencesTypical loading/unloading sequences, having unevenly distributed cargo between cargo holds, shall beincluded in the loading manual in accordance with Pt.6 Ch.1 Sec.4 [10.3].

4.2 Loading conditions for primary supporting members4.2.1 GeneralThe design loading conditions for direct strength analysis of primary supporting members shall envelope allloading conditions included in the loading manual, as required in Pt.3 Ch.4 Sec.8 [2] and [4.1].

Guidance note:The seagoing FE design load combinations given in Pt.6 Ch.1 Sec.4 [4.2.8] for HC(M) ships may be used as guidance for ballastloading conditions and dry bulk cargo loading conditions.



5.1 Loading manual and loading instrumentThe ships shall belong to category I. Ships intended for the carriage of homogeneous loads only, may uponrequest, be considered according to the requirements for ships in category II.


6.1 Minimum thickness6.1.1 Minimum thickness of inner bottom in cargo holdsThe minimum net thickness, in mm, of inner bottom plating in cargo holds shall be in accordance with Pt.3Ch.6 Sec.3 [1.1.1] with:



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a = 7.0b = 0.05.

6.2 Plating6.2.1 Plating subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.4 [1] shall be complied with, applying the additional design loadsets given in Sec.2 [5.1].

6.3 Stiffeners6.3.1 Stiffeners subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.5 [1] shall be complied with, applying the additional design loadsets given in Sec.2 [5.1].


6.5 Intersection of stiffeners and primary supporting members6.5.1 Connection of stiffeners to primary supporting membersThe requirements for connection of stiffeners to primary supporting members shall comply with Pt.3 Ch.6Sec.7 [1], including the internal pressure due to dry bulk cargo given in Sec.2 [3].





7.1.2 ApplicationCargo hold analysis of midship region is mandatory irrespective of the ship’s length.


7.1.4 Internal loadsBulk pressures and shear loads shall be applied to the FE model in accordance with Sec.2 [3].



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8 Buckling

8.1 Hull girder bucklingThe requirements given in Pt.3 Ch.8 Sec.3 shall be complied with, applying the additional design load setsgiven in Sec.2 [5.1].

9 Fatigue

9.1 General

9.1.1 Fatigue assessment shall be carried out for ships having a length L of not less than 90 m, inaccordance with Pt.3 Ch.9 using detailed requirements in the following subsections.



9.2 Prescriptive fatigue strength assessment9.2.1 GeneralWithin the cargo region, the fatigue life of longitudinal end connections in way of web frames and transversebulkheads shall be assessed in accordance with DNV-CG-0129 Sec.4.



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SECTION 9 GREAT LAKES BULK CARRIERSSymbolsFor symbols not defined in this section, see Pt.3 Ch.1 Sec.4 [2].

1 Introduction

1.1 IntroductionThese rules apply to ships primarily intended for the carriage of solid bulk cargoes operating on the GreatLakes and St Lawrence river.

1.2 ScopeThis section describes requirements for arrangement, hull strength, hull equipment and stability, including:

— general arrangement design, see [2]— structural design principles, see [3]— loads, see [4]— hull girder strength, see [5]— hull local scantling, see [6]— finite element analysis, see [7]— buckling, see [8]— fatigue, see [9]— special requirements, see [10]— hull equipment, supporting structures and appendages, see [11]— openings and closing appliances, see [12]— stability, see [13].

1.3 Application

1.3.1 These rules are applicable to ships primarily intended to carry dry cargoes in bulk designed tooperate within the limits of the Great Lakes and the St. Lawrence River to the seaward limits defined byAnticosti Island, and having single deck with a double side skin construction and double bottom constructionthroughout the cargo hold region.

1.3.2 Ships complying with the requirements given in this section will be assigned the ship type classnotation Great lakes bulk carrier.


2.1 Subdivision arrangement2.1.1 Watertight bulkhead arrangementThe requirements given in Pt.3 Ch.2 Sec.2 shall be complied with, with the following exemption: Pt.3 Ch.2Sec.2 [1.1.4] is not mandatory.



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2.1.2 Collision bulkheadThe requirements for collision bulkhead given in Pt.3 Ch.2 Sec.2 [4] shall be complied with, applying aminimum distance of 0.04 LLL aft of the reference point.


3.1 Corrosion additionsThe corrosion addition for one side of structural members within a ballast water tank shall be taken as forfresh water, fuel oil and lube oil tank given in DNV-CG-0182 Sec.4 Table 1.

3.2 Structural arrangementThe requirements given in Sec.2 [2] shall be complied with, where applicable.

4 Loads

4.1 General4.1.1 Service area restrictionThe loads for strength assessment given in Pt.3 Ch.4 and Sec.2 [3] shall be established applying thereduction factors given by the service area notation RE.The loads for fatigue assessment given in Pt.3 Ch.4 is not mandatory.

4.2 Standard design loading conditions4.2.1 GeneralThe standard design loading conditions given in [4.2.2] shall be considered in addition to the standardloading conditions given in Pt.3 Ch.4 Sec.8 [1].

4.2.2 Dry bulk cargo loading conditionHomogeneous cargo loaded condition shall be included in the loading manual where the cargo densitycorresponds to all cargo holds, including hatchways, being 100% full at scantling draught.

4.3 Loading conditions for primary supporting membersThe loading conditions for direct strength analysis of primary supporting members shall envelope all loadingconditions included in the loading manual, as required in Pt.3 Ch.4 Sec.8 [2] and [4.2], with loads inaccordance with [4.1.1].

Guidance note:The seagoing FE design load combinations given in Pt.6 Ch.1 Sec.4 [4.2.8] for HC(M) ships may be used as guidance for ballastloading conditions and dry bulk cargo loading conditions.


4.4 Hold mass curvesFor ships with HC notation, the hold mass curves for seagoing and harbor conditions shall be in accordancewith Pt.6 Ch.1 Sec.4 [5].



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Additional hold mass curves for such ships sailing in load conditions in the Great Lakes within the operationlimit as given in [1.3.1], if requested, shall be taken as the average of the above seagoing and harbor holdmass curves.


5.1 Vertical hull girder shear strength5.1.1 Shear force correctionHull girder shear strength assessment, including shear force correction, shall be carried out in accordancewith Sec.5 [5.2].

5.2 Hull girder yield check5.2.1 Hull girder stress componentsThe additional hull girder strength requirements for ships with large deck openings given in Pt.3 Ch.5 Sec.3[3] are not mandatory.

5.3 Hull girder ultimate strength checkThe hull girder ultimate strength requirements given in Pt.3 Ch.5 Sec.4 are not mandatory.


6.1 Plating6.1.1 Plating subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.4 [1] shall be complied with, applying the additional design loadsets given in Sec.2 [5.1], with loads in accordance with [4.1.1].

6.2 Stiffeners6.2.1 Stiffeners subject to lateral pressureThe requirements given in Pt.3 Ch.6 Sec.5 [1] shall be complied with, applying the additional design loadsets given in Sec.2 [5.1], with loads in accordance with [4.1.1].

6.3 Primary supporting membersFor primary supporting members not assessed in accordance with [7.1], the requirements given in Pt.3 Ch.6Sec.6 [2] shall be complied with, applying the loading conditions for PSM given in [4.2], with the additionaldesign load sets given in Sec.2 [5.1] and loads in accordance with [4.1.1].

6.4 Intersection of stiffeners and primary supporting members6.4.1 Connection of stiffeners to primary supporting membersThe requirements for connection of stiffeners to primary supporting members shall comply with Pt.3 Ch.6Sec.7 [1], including the internal pressure due to dry bulk cargo given in Sec.2 [3], with loads in accordancewith [4.1.1].



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7.1.2 ApplicationCargo hold analysis of midship region is mandatory irrespectively of ship’s length.


7.1.4 Internal loadsBulk pressures and shear loads shall be applied to the FE model in accordance with Sec.2 [3], with loads inaccordance with[4.1.1].

8 Buckling

8.1 Hull girder bucklingThe requirements given in Pt.3 Ch.8 Sec.3 shall be complied with, applying the additional design load setsgiven in Sec.2 [5.1], with loads in accordance with [4.1.1].

9 Fatigue

9.1 GeneralThe fatigue requirements given in Pt.3 Ch.9 are not mandatory.

10 Special requirements

10.1 Bow impactRequirements for strengthening for bow impact loads as given in Pt.3 Ch.10 Sec.1 are not mandatory.

Guidance note:Operational experience indicates that navigation in the seaway locks and in light ice may cause contact damages to platingand framing in fore and aft shoulder areas. In order to reduce the risk of local structural deformations, it is advised that this isconsidered in the design.




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10.2 Bottom slammingRequirements for strengthening for bottom slamming loads as given in Pt.3 Ch.10 Sec.2 are not mandatory.

10.3 Stern slammingRequirements for strengthening for stern slamming loads as given in Pt.3 Ch.10 Sec.3 are not mandatory.

11 Hull equipment, supporting structures and appendages

11.1 Anchoring and mooring equipment11.1.1 Equipment numberThe equipment number, EN’, is given by the formula:

EN’ = 0.3 LBD + α + b

where:

a = addition for the 1st tier of superstructure and deck houses17.6% of volume of 1st tier (length × breadth × height)

b = addition for the 2nd tier of deckhouses and other erections13.2% of the volume of the 2nd tier (length × breadth × height).

11.1.2 AnchorsTwo bower anchors in accordance with Pt.3 Ch.11 Sec.1, applying equipment number given in [11.1.1], shallbe provided.A stern anchor shall be fitted as required by the St. Lawrence Seaways Authority.

11.1.3 Anchor chain cablesA stud-link chain cable of total length 330 m in accordance with Pt.3 Ch.11 Sec.1 shall be provided onboard.

11.2 Supporting structure for deck equipment and fittings11.2.1 Shipboard fittings and supporting hull structures associated with towing and mooringRequirements for supporting structure of deck fittings equipment and fittings as given in Pt.3 Ch.11 Sec.2 arenot mandatory.

11.3 Bulwark and protection of crewRequirements for supporting structure of deck fittings equipment and fittings as given in Pt.3 Ch.11 Sec.2 [5]are not mandatory.

11.3.1 Minimum heightThe minimum height of bulwarks or guard rails given in Pt.3 Ch.11 Sec.3 [1.2]may be disregarded and shallbe at least 900 mm in height.

11.3.2 Protection of the crewThe requirements for guard rails given in Pt.3 Ch.11 Sec.3 [3.1] are not mandatory.Guard rails shall be fitted, complying with minimum one of the following:



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— three courses shall be fitted as a minimum. The spacing between lowest course and ship's deck shall notexceed 230 mm. The spacing between courses shall not exceed 380 mm

— if the sheer strake projects at least 200 mm above the deck, two courses shall be fitted as a minimum.The spacing between the lower course and the sheer strake or the upper course shall not exceed 380 mm.

11.3.3 Gangways, walkways and passagewaysThe requirements for gangways, walkways and passageways given in Pt.3 Ch.11 Sec.3 [3.2] are notmandatory.The ship shall have lifelines, gangways or under deck passages for the protection of the crew while passingto and from their accommodation spaces, the machinery space and all other spaces used in the normaloperation of the vessel.Whenever bulkhead openings are closed, other access shall be provided for the crew to reach accommodationspaces or machinery or other working spaces in enclosed superstructures that are bridges or poops.If an exposed part of a freeboard deck is in way of a trunk, guardrails shall be fitted for one-half the length ofthe exposed part.

12 Openings and closing appliances

12.1 GeneralOpenings and closing appliances shall comply with the requirements given in Pt.3 Ch.12, applying theCanadian Load Line Regulations instead of the International Load Line Regulations.

12.2 Small hatchways and weathertight doors12.2.1 Height of hatch coamingsThe height above deck of hatchway coamings shall be at least 460 mm in position 1 and at least 300 mm inposition 2. The requirements to hatch coaming heights given in Pt.3 Ch.12 Sec.2 [2.3] are not mandatory.

12.2.2 Weathertight doors - sill heightsDoors in position 1 or position 2 shall have a sill height, measured from the deck, of at least 300 mm. Therequirements to sill heights given in Pt.3 Ch.12 Sec.2 [4] are not mandatory.

12.3 Cargo hatch covers/coamings and closing arrangements12.3.1 Heigh of hatch coamingsThe height above deck of hatchway coamings shall be at least 460 mm in position 1 and at least 300 mm inposition 2. The requirements to hatch coaming heights given in Pt.3 Ch.12 Sec.4 [5] are not mandatory.

12.3.2 Hatch coversThe requirements for hatch covers given in Pt.3 Ch.12 Sec.4 shall be complied with, applying the load modeland strength requirements given in the Canadian Load Line Regulations instead of the International Load LineRegulations.The corrosion additions given in Pt.3 Ch.12 Sec.4 Table 1 are not mandatory.



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12.4 Side, stern and bow doors/ramps12.4.1 Lower edge of side doors, stern and bow doors/rampsThe lower edge of side door and other similar openings shall not be below a line drawn parallel to thefreeboard deck at side that has the upper edge of the uppermost load line at its lowest point.

12.5 Tank access, ullage and ventilation openings12.5.1 Air pipesAir pipes shall have a coaming height of at least 760 mm on the freeboard deck, 600 mm on raised quarterdecks and 300 mm other superstructure decks.

12.5.2 VentilatorsVentilator coamings shall be at least 760 mm above deck in position 1 and at least 600 mm above deck inposition 2.Ventilator openings shall have permanently attached weather tight means of closing.The requirement for weather tight closing appliances is not applicable for ventilators in position 1 withcoamings that extend 3.8 m or more above the deck or to ventilators in position 2 with coamings that extend1.8 m or more above deck.

12.6 Machinery space openingsThe lower edge of any access opening in the casing shall be at least 300 mm above the deck.If the opening is a funnel or machinery space ventilator that needs to be kept open for the essentialoperation of the vessel, then the coaming height shall be at least 3.8 m in position 1 and 1.8 m in position 2.

12.7 Scuppers, inlets and discharges1) Every discharge pipe passing through the shell from spaces below the freeboard deck shall comply with

either a) or b) below:

a) have an automatic non-return valve fitted at the shell with a positive means of closing that isoperable

i) from above the freeboard deck, orii) from a readily accessible location if the discharge originates in a space that is crewed or

equipped with a means of continuously monitoring the level of bilge water

b) have two automatic non-return valves, one of which is fitted at the shell and one inboard that isaccessible for examination when the vessel is in service.

2) Every discharge pipe that passes through the shell from within an enclosed superstructure, or fromwithin a deckhouse that protects openings to below the freeboard deck, shall comply with either a) or b)below:

a) meet the requirements set out in paragraph 1) a) or b)b) have an automatic non-return valve fitted at the shell, if the discharge originates in a space that is

regularly visited by the crew.

3) Every scupper, drain or discharge pipe that passes through the shell above the summer fresh waterload line at a distance that is less than the greater of 5% of the breadth and 600 mm, shall have anautomatic non-return valve fitted at the shell.

4) Item 3) does not apply in respect of a scupper, drain or discharge pipe that originates above thefreeboard deck, if the part of the pipe that is between the shell and the freeboard deck has substantialthickness.



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5) In crewed machinery spaces, every main and auxiliary sea inlet and discharge necessary for theoperation of machinery shall have a valve with a positive means of closing that can be controlled locally.

6) The valves required by this section to have positive means of closing shall have indicators at theoperating position to show whether the valve is open or closed.

12.8 Freeing portsThe freeing port area shall be calculated as described in Pt.3 Ch.12 Sec.10 [2.1] with due attention toadjustments due to the height of the bulwark as given below:The freeing port area shall be increased by 0.04 m2 per metre of length of the well, for each metre that theheight of the bulwark exceeds:

— 600 mm, in the case of vessels that are 73 m in length or less— 1200 mm, in the case of vessels that are 146 m in length or more, and— in the case of vessels that are of intermediate length, the height obtained by linear interpolation betweenthe heights set out in points above.

13 Stability

13.1 GeneralThe requirements for stability given in Pt.3 Ch.15 shall be complied with, applying Canadian flag stabilityrequirements.



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CHANGES – HISTORIC

July 2020 edition

Changes July 2020, entering into force 1 January 2021Topic Reference Description

Sec.6 [2.1] One paragraph deleted.CSR

Sec.6 [2.1.3] New paragraph included.

July 2019 edition


Sec.1 Table 2 Introduction of reference to the class notation RSD. See Pt.6Ch.1 Sec.8.

Introduce RSD notation as anoptional choice for Generaldry cargo ship and Multi-purpose dry cargo ship Sec.5 [7.1] to Sec.5

[7.4.2]Introduction of class notation RSD for MPV. Therefore formertext parts of Pt.5 Ch.1 Sec.5 [7.1.2 - 7.1.8] with requirementsfor the global FEA have been shifted to Pt.6 Ch.1 Sec.8.Furthermore corresponding updates in Sec.5 [7.1] and Sec.5[7.3] have been introduced and a reference to DNVGL-CG-0127in Sec.5 [7.2] was shifted to Sec.5 [7.1].

Sec.2 [1.3.2] Reference to Pt.3 with respect to cargo temperatures higherthan 80°C and colder than 0°C for CSR vessels are made.

Clarification of rules

Sec.2 [1.3.3] Reference to Pt.3 for CSR ships intended to operate in areaswith low air temperatures is added.

Openings in decks and outershell

Sec.2 [2.3] [6.3.4] from Pt.3 Ch.3 Sec.6 moved to Sec.2 [2.3].

July 2018 edition


Sec.7 [3.3.5] This is moved from Pt.6 Ch.1 Sec.5 [7.1.9].Maintenance of rules for orecarriers. Sec.7 [5] The prescriptive requirements for shear force correction of ship

side are included.

Part 5 Chapter 1 Changes – historic


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July 2017 edition

Amendments January 2018Topic Reference Description

Add missing variable andchange variable name in Sec.5[7.2.8].

Sec.5 [7.2.8] In the formula for the static and dynamic force Fc-z the missingvariable lp has been added and the variable BTop corrected.


Sec.5 Reduction of permissible still water bending moment and shear forcefor harbour condition, to comply with the acceptance criteria for AC-Iaccording to Pt.3 Ch.1 Sec.2 Table 1 and Pt.3 Ch.7 Sec.3 Table 1.

Sec.5 Modification of lp and introduction of Δ Z for application of formula inSec.5 [7.2.7] and Sec.5 [7.2.8].

Sec.5 [5.2.3] Aligned with update in Pt.3 Ch.5 Sec.2 [2.3.1].

Sec.5 Table 2 Use of 10-8 probability level for ULS and correct speeds. In alignmentwith Pt.3 Ch.1 Sec.2 [5.3.2] and Pt.3 Ch.1 Sec.2 [5.3.3].

Sec.5 [7.1.6] Consideration of all loading conditions with an equal fraction results in amore realistic fatigue life more in line with Pt.3 Ch.9 Sec.4 [3].

Sec.5 [7.1.7]

Sec.5 [7.1.8]

Alignment of the acceptance criteria with the 10-8 probability level.

Sec.5 [7.2.6]

Sec.5 [7.2.7]

Sec.5 [7.2.8]

Introduced simplified approach by which shear pressures or forces inlongitudinal can be ignored.

Sec.5 [7.2.7]

Sec.5 [7.2.8]

Introduced requirement to consider the tipping moment, generated bycargo resting on hatch covers, in both assessment of cargo hold andFEA, for consistency between these.Introduced requirement to consider more realistic forces on hatch coverson weather deck.

Application of global FEAfor general dry cargoships and multi-purposedry cargo ships.

Sec.5 [7.3] Deleted paragraph describing embedded cargo hold analysis.

Correction of design loadsets table.

Sec.3 [3.2.1] Changed Sec.3 Table 3 to match static load conditions with the correctload scenario definition and acceptance criteria.

Correction of stiffenerlength applied forsection modulusrequirements.

Sec.3 Table 4 Replaced l with lbdg in calculation of coefficient K3



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October 2015 editionThis is a new document.The rules enter into force 1 January 2016.

Amendments January 2016

• Sec.6 Bulk carriers— [2.1.2]: Clarification on how to handle CSR vessels has been inserted.— [2.1.3]: Applicable regulations for access to tanks and compartments (IACS UI 191 and SOLAS Reg.II-1/3.6) has been inserted.



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DNV-RU-SHIP Pt.5 Ch.1 Bulk carriers and dry cargo ships

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Transcript of DNV-RU-SHIP Pt.5 Ch.1 Bulk carriers and dry cargo ships