03 Offshore Interface Procedure AJS

8/11/2019 03 Offshore Interface Procedure AJS

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Chapter: HNDB-SSM-03

Revision: 2Page: 1 of 14Date: 01-04-2012

OFFSHORE INTERFACE PROCEDURE - AJS

Harsco Infrastructure B.V. George Stephensonweg 15 P O Box 160 3130 AD Vlaardingen

Telephone 010 - 445 54 44 Fax 010 - 435 14 03

______________________________________________________________________________________________

Property of Harsco Infrastructure B.V. in Vlaardingen (NL)Copying with the intention to share the information with third parties, in any form whatsoever, is not allowed

without the owners approval.

Scaffolding: design and design assessment/ verification

Special scaffolding constructions

Contents

1. Purpose2. Area of application

3. Definitions4. Procedure5. Tasks, accountabilities and competences6. Design and assessment basics and considerations7. References

Annexure 1: Standard scaffolding criteria


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1.0 Purpose

The purpose of this procedure is to record the procedure that should be followed by HarscoInfrastructure and AJS to guarantee the integrity of the special scaffolding at all times. Thus strivingfor a practical and clear procedure of designs and assessments of special scaffolding for allparties.

2.0 Area of application

This procedure applies to all offshore locations where Harsco infrastructures, commissioned by AJS,must design and supply special scaffolding.Note: The integrity of standard e.g. normal" scaffolding can always be assessed using the setstandard drawings/calculations and the tables determination of standard loads [1] on site.

3.0 Definitions

Standard scaffolding (2): Scaffolding that does not comply with any of the points indicated inAnnexure 1: Standard scaffolding criteria.

Rolling scaffold: Scaffolding equipped with wheels constructed from prefabricatedcomponents according to NEN-EN 1004.

Mobile scaffolding: Scaffolding on wheels with one or more work floors.Complex scaffolding (2): Scaffolding that falls outside the abovementioned scope of standard

scaffolding.


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4.0 Procedure: Coordination of designs and design assessment

IDno.

Actions & productresult

HarscoInfrastructure

AJSimplementatio

AJSstruct.engin.

Basic info./referralto procs & instrs

1. Send request for special scaffolding

Onshore and/or Offshore location

exe

2. Receipt of request, incl. projectdetails

exe PRO-IN/001Walkthrough procedur

3. Design, drawing and

calculating the special scaffoldingDrawing for approval

exe PRO-ST/101

Design procedure

4. Verification and corrections to

drawings

exe Ditto

5. Processing corrections in drawings

Drawing for approval

exe Ditto

6. Sending drawings and calculationreport for verification, assessment a

authorization

exe

7. Verification and corrections of

drawings and reports

exe

8. Processing of corrections in

drawings and calculations

Drawing for approval

exe

9. Verification and corrections of

design, drawings and reports

exe

10. Processing of corrections in

drawings and calculations;Drawing for approval

exe

11. Authorization app app

12. Distribution of drawings andreports;

Drawing work drawing

exe

exe = Execution * = Execution in Maintenance,app = Authorization Operations, Engineering,

(through signature + date on drawing) Modificationsinf = informing


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5.0 Tasks / Responsibilities / Competencies

Party IDno

Task Competency Responsibilities

AJS execution 1 Sending applicationto Harsco Infrastructure Supervisor

Offshore

Harsco Infrastructure

Supervisor

2 Receipt of application and proje

details


Engineering

3 Based on project details, designs,

drawings andcalculations

Designs according to

design procedure

Harsco InfrastructureProject manager/

Supervisor

4 Assessment of scaffolding designfor assembly,

safety, quality and contract

Proposals foramendments

and acceptance of1stdesign

Approval based ondetails and request

Harsco InfrastructureEngineering

5 Changes to drawingsand in calculations.

Drafting a calculations report

Inform Supervisor


Supervisor

6 Distribution of drawings and

calculations for approval

AJS execution 7 Receipt of drawingsand calculations

Assessment ofdesign based

on request

Design in accordancewith request


Engineering

8 Processing of corrections in

drawings

AJS execution 9 Inspection of processed

corrections; send toAJS Engineering

Acceptance of

design

Design in accordance

with request


Engineering

10 Assessment of drawings

and calculations and

drafting of technical note

Assessment of

considerations and

standing and anchorforces as loads on the

construction/platform

Approval/rejection of

feasibility with regard to

loadbearing capacity ofconstruction/platform


Engineering

11 Processing of corrections in

drawings en calculations;Distribution of drawings and

calculations for verification

AJS StructuralEngineering

12 Inspection of processedcorrections; distribution of technicnote

Acceptance of desigand calculationauthorization on

technical note

Feasibility with regard tocarrying capacity ofconstruction/platform


Supervisor

13 Receipt of confirmation of

approval.Distribution of working drawings

and calculation report to executiscaffolders

(for scaffolding books and

AJS execution

Distribution of

information

Instructions to scaffolders


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6.0 Basics and considerations for design and assessment

6.1 Scaffolding drawings

Harsco Infrastructure will make drawings of the special scaffolding on which the views, dissections anddetails of the constructions to be assembled are indicated. The stand distances, work floors, anchors,diagonal context are all necessary information for the executing scaffolders. The scaffolding structurewill be assembled using the drawings.We emphasize that the version number and the date on the standard drawing should correspond.

6.2 Design assessment

Scaffolding constructions on offshore platforms in the Dutch Sector of Continental Plat mustcomply with the following regulations:1. Occupational Health Decree: article 3.16, 7.4, 7.4a, 7.6, 7.11a, 7.17c and 7.34

Policy regulation: 3.16, 7.4-4, 7.4-5 and 7.34.2. NEN-EN 74-1:2005 Couplings, cotter pins and base plates for steel tube scaffolding3. NENEN 39:2001 Steel tubes for support framework and system scaffolding4. NEN-EN 12810-1:2003 Wall scaffolding manufactured from pre-fabricated components -

Part 1: Product specifications5. NEN-EN 12810-2:2004 Wall scaffolding manufactured from pre-fabricated components -

Part 2: Special method of a constructive design6. NEN-EN 12811-1:2003 Temporary construction site equipment - Scaffolding - Performance

requirements and general design7. NEN-EN 12811-2:2004 Temporary construction equipment - Part 2: information on materials8. NEN-EN 12811-3:2002 Temporary construction equipment - Part 3: Load test9. NEN 6702:2001 TGB 1990 Loads and distortions10. Mining Act 1964 (153,154)11. Further Regulations Mining Act 1974 (107)12. Mining Act Continental Plat (103, 104)13. Further Regulations Mining Act Continental Plat (107)

Furthermore, the following will be used with the design and assessment of this scaffolding

construction:

14. Harsco Infrastructure Load Manual15. Harsco Infrastructure Product Information Manual16. CUPLOK Zulassung Z-8.22-208; CUPLOK junction


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6.3 Geometry of the calculation models

Harsco Infrastructure uses the calculation program "STAB2F" and/or SCIA ESA PT for the analysisof static calculations.

STAB2F is a 2D program used to calculate rod constructions in a level. It is based on the so-calledtransfer method where three transfer directions are allowed per junction (X, Z and rotation).

SCIA ESA PT is a 3D program used to calculate rod constructions. Six transfer directions are allowedper junction (X, Y, Z and rotation x, y, z).

With Harsco Infrastructure, the 2nd order will be elastic-plastic calculated in accordance with thestandards NEN-EN 12811-1.This means that internal forces and torques are determined according to the Elastic Calculationmethod and the rigidity inspection takes place according to the plastic criteria.The model is drafted using the accompanying drawing.

6.3.1 Model design

Stab2F:

The calculation model is drafted based on the following points:

1. Model dimensions as indicated in the relevant drawing.2. Applying the correct material characteristics, connection springs and geometric

imperfections.3. The weight of all components standing perpendicular on the calculation model is imported as

junction loads. The weight of the couplings connected on two stands is taken in half per stand.This also applies for braces, guardrails and side plates.

4. The weight of all couplings and braces, lying on the plane of the calculation model areimported as a spread load. The weight of the stands is imported in this level as junction loads.

5. The weight of the floor and the load is applied as equal load on the couplings and/or pointloads to the connection with the stands. Here the orientation of the floor part in the plane ofthe calculation model is taken into account.

6. With undressed scaffolding the wind load is imported on all components (except stands) as

horizontal point loads at the connection between the stands and the couplings. This point loadis calculated in the height per stroke. The wind load on the stands is imported as a dividedload over the entire length of the stands.

7. With coated scaffolding, a divided wind load on the stands is used for calculation.

SCIA ESA PT:


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1. Model dimensions as indicated in the relevant drawing.2. Applying the correct material characteristics, connection springs and geometric

imperfections.3. The weight of the modelled tubes is automatically defined by the calculation program. To

take the weight of the couplings into account its own weight is increased by a factor1,2.4. The weight of the floor and the load is applied as equal load on the couplings and/or point

loads to the connection with the stands. Here the orientation of the floor parts in the level ofthe calculation model is taken into account.

5. With undressed scaffolding the wind load is applied as divided load on all components.6. With dressed scaffolding a plane load generator is used. Depending on the wind resistance

of the dressing, a wind pressure percentage is calculated.

NOTE:1) The wind pressure on the guardrails causes a negligible torque in the stands. Therefore the wind loads will be

applied as connection load at the intersecting point between the stands and floor couplings.2) The so-called splash zone (from water surface to cellar deck) possible occurring wave and current forces,

are not taken into account.

6.3.2 Geometric imperfections

According to NEN-EN 12811-1 (10.2.2) geometric imperfections consist of tilt and preliminarycurvature and it should be taken into account in the calculation. Harsco Infrastructure uses thefollowing values for geometric imperfections for scaffolding calculations:

Tilting foot spindles with respect to stands: tan() = 0,0135Relative tilt of stands: tan() = 0,01 (alternately +0,005/-0,005)

Preliminary curvature of stands: 0/l = 1/200 = 0,005

With the calculations the preliminary curvature is automatically aligned to the unfavourable side.


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6.4 Profile and material characteristics

Scaffolding material used by Harsco Infrastructure is described on Harsco Infrastructure Intranet;Engineering; Product Information.

6.4.1 Materials

stands and links, tube 48,3 * 3,2 mm, material S355 system braces, tube 48,3 * 2,9 mm, material S235

loose tubes and tube-lock tubes 48,3 * 3,2 mm, material S235

diagonals with loose links, tube 48,3 * 3,2 mm, material S235

consoles and development support, tube 48,3 * 3,2 mm, material S235 steel or aluminium lattice trusses, centre to centre. height 400 mm

anchor tubes, tube 48,3 * 3,2 mm, material S235

class B scaffolding connections (in accordance with NEN-EN 74) Floor components: - aluminium platforms should be used for scaffolding through load

class 2.- Steel parts should be used in all load classes (besides: 2,50m through class 5;

3,00m through class 4).- Wooden scaffolding parts are suitable for use in all load classes.

6.4.2 Connecting springs

The applicable stiffness value of the Cuplok junction and loose scaffolding connections areimported as connection springs in the calculation model.The following connection springs are used:

Table 1: Connection springs.

Connecting spring Rigidity Mu,d ; Fu,d

Cuplock junction (rotation)* 11800-28,65M [kNcm/rad] 228,8 [kNcm]

Cross-head junction (rotation) ** 1400 [kNcm/rad] 80 [kNcm]

Cross-head junction (torsion) ** 2000 [kNcm/rad] 20 [kNcm]

Cross-head junction (pull/push) ** 100 [kN/cm] 15 [kN]Swivel junction (pull/push) ** 25 [kN/cm] 8,5 [kN]

Foot spindle (rotation) *** 2000 [kNcm/rad] 170 [kNcm]

* acc. [14] ** acc. [DIN 4420-1] *** acc. [6], 10.2.3.2


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6.4.3 Material factor

The rigidity and maximum load of the materials and the connection springs is shared by a materialfactor. This material factor (M) is 1,1 (NENEN 12811-1). With Mthe imprecision in structure andcomposition of the material is taken into account.

6.5 Load groups

When calculating the strength of scaffolding, the following load groups should be taken intoaccount:

Tare weight Work load Wind load Particular loads

6.5.1 Tare weight

The tare weight of the components of the construction, or in the relevant cross-section, is includedin the calculations as described in paragraph 6.3.1, whereby:

Own weight tube = 3.9 kg/mOwn weight wood (50mm) = 6 kg/m; 30 kg/m2

6.5.2 Work load

The work load on the scaffolding depends on maximum allowed work load indicated on thescaffolding drawing. This amounts to 1.50 kN/m2(class 2) or 3.00 kN/m2(class 4) where the otherwork floors may not be loaded simultaneously with the upper work floor


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6.5.3 Wind load

There are 2 wind loads which should be taken into account, the work wind (to wind force8 Bft) and the maximum wind force.The thrust value for the work wind amounts to 0.2 kN/m2in accordance with NEN-EN 12811-1. Forthe maximum wind the thrust value is indicated by the NAM and this amounts to 1.25 kN/m 2It is assumed that these thrust values are constant and therefore does not vary over the height ofthe scaffolding construction.

Due to the temporary nature of the scaffolding construction the reduction factor for the extremevalue of the variable load for the wind amounts to ( t) 0,57.

The wind load on the wind catching surface of the scaffolding construction is determined usingthe following formula (NEN 6702):

Fwind= cdimx cindexx ceqx 1x pwx A x t

where:cdim = Factor that brings the dimensions of the construction works into account.cindex = Wind form factors. In this case 1,2 of which 0,8 is pressure on the front side and 0.4

suction on the rear end.ceq = pressure equalizing factor1 = Increasing factor that takes the dynamic influence on the wind in the wind direction on

construction works into account.pw = Thrust.A = Considered surface on which the wind load works.t = Correction factor for the reference duration.

6.5.4 Special loads

Horizontal work load

It could occur that a scaffolding construction is inside and therefore experiences no wind load. Inthis case the work floor, where the work load is applied, should be loaded with a horizontal workload. This load amounts to the highest value of 0,3 kN or 2,5% of the divided work load.

Hoist loadThe hoist load is a separate load group. With hoist activities an extra dynamic load factor shouldbe taken into account. This is simulated by increasing the weight of the load to be hoisted by 20%.

Dynamic loadThe dynamic effect of a load that is placed horizontally over the scaffolding is modelled by 10% ofthe weight of the load as horizontal power.


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6.6 Load combinations and load factors

According to the standards NEN-EN 12811-1 the calculations should be split in two loads, namely: Work wind situation Maximum wind situation

There are furthermore 2 checkpoints for both combinations, namely:

Calculations on strength Tilting calculations (in the event of a detached construction)

With every situation it will be indicated which load groups apply and which load factors should be

applied.

6.6.1 Work wind situation

Calculations on strength

Name of load: Load factor (F):

Tare weight 1,2100% work load on unfavourable floor 1,550% work load on floor immediately below 1,5possible special loads 1,5

work wind 1,5

Tilting calculations

Name of load: Load factor (F):Tare weight 0,9 (positive) or 1,2 (unfavourable)work load on unfavourable floor 0 (positive) or 1,5 (unfavourable)possible special loads 0 (positive) or 1,5 (unfavourable)work wind 1,5ballast 0,9

If the load described above increases the tilting effect, the value unfavourable must be used. If

the tilting of the construction is countered by the relevant load the positive value is used.


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6.6.2 Maximum wind situation

Calculations on strength

Name of load: Load factor (F):Tare weight 1,2Work load on unfavourable floor 1) 1,5Maximum wind 1,5

Tilting calculations

Name of load: Load factor (F):

Tare weight 0,9 (positive) or 1,2 (unfavourable)Work load on unfavourable floor 1) 0 (positive) or 1,5 (unfavourable)Maximum wind 1,5Ballast 0,9

1) Percentage of the work load depending on the load class of the scaffolding.Class 3: 25%Class 4: 50%

6.7 Testing

The most important details are reflected in the calculations report:

1. The materials used, cross-sections and connection springs are reflected with the import details. Thecomplete cross-section can be seen on the graphic printout.

2. The following points are reflected with the calculation results: support reactions the plastic material control (Nachweiss plastic), according to the following formula

dpldpl

dNpl

N

N

M

M

,,

,,

2

cos

(NEN-EN 12811-1, 10.3.3)

inspection of the connection springs of both the switches and braces.

3. The maximum material use (Ausnutzung) is indicated. This may not be more than 1,00.


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4. The bending capacity of the pin connection between 2 cuplock stands is controlled separatelyusing the maximum occurring torque at locations where such stand-stand connections can beplaced. The bending capacity amounts to 116 kNcm in the extreme limit position, according to[14].

5. The pressure in the braces assembled in the cross section should be tested manually on themaximum pressure capacity according to [14].Stab2F namely does not take the eccentricity that is caused by the connections into account.SCIA ESA PT does.

6. The scaffolding construction is also checked for shifting.For this the following friction coefficients are used, in accordance with NEN-EN 12811.

Steel wood 0,5Wood concrete 0,8Steel concrete 0,3

6.7.1 Testing AJS Engineering

The testing of anchor and stand loads by AJS engineering takes place based on the loadcapacity and load ability of the construction and/or platforms on which/whereon the special

scaffolding construction is confirmed. They will furthermore verify the assumed considerationswith the model forming of the calculation.

7.0 References

1. Harsco Infrastructure; Standard information Scaffolding construction SSM manualChapter 7

2.

Harsco Infrastructure; Criteria standard scaffolding SSM Manual Chapter 3, page 14


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Annexure I: Annexure 1: standard scaffolding

When none of the following points are relevant it involves a standard scaffolding construction.When one or more points apply it involves special scaffolding which must besketched/calculated.

Criteria

1 Scaffolding higher than 24 meters work floor height

2 Floor load more than 3 kN/m2

3 More than 1,5 work floors at the same time fully loaded in accordance with scaffoldingclasses.

4 Scaffolding with console with floor width of extension

5 Nets, canvas or shrink wrap coating

6 Stroke height exceeding 2 meter

7 Hanging scaffolding

8 Extension scaffolding

9 Detached scaffolding outside

10 Support scaffolding

11 Walkways and bridges

12 Gangways13 Scaffolding cap

14 Scaffolding for hoisting activities

15 Storage scaffolding

16 With mechanical transport (other than manually) on the scaffolding

17 Deviating anchor pattern

18 Scaffolding with counterweights or ballast / buttress / tethering

19 Scaffolding in (flowing) water

20 Scaffolding with public accessibility / events

21 Scaffolding on slopes / angled roofs with slope angle:

22 Scaffolding for goods / persons / passenger and goods lift

23 Movable steel scaffolding (not a rolling scaffolding)

24 Lifting scaffolding25 Scaffolding on spider deck level/splash zone

03 Offshore Interface Procedure AJS

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