Code of Procedure v1.0 DraftFinal

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C O

D E

O F P

R O C E D U R E

Federal Republic of NigeriaFederal Ministry of Works

Highway Manual Part 1: Design

Code of Procedure

2013



Highway Manuals Code of Procedure

Federal Ministry of Works i

CODE OF PROCEDURE

TABLE OF CONTENTS

Chapter 1.

General Information ........................................................................... 1

1.1 Introduction ................................................................................................ 1

1.2 Code of Procedure to link to Highway Manuals .......................................... 1

1.3

Definitions .................................................................................................. 2

1.4

Phases of a Highway Project ..................................................................... 2

1.5 Responsibilities for Highway Projects......................................................... 5

Chapter 2. Identification Phase ............................................................................ 6

2.1 Project Identification ................................................................................... 6

2.2

Network Monitoring .................................................................................... 6

2.3 Land Use And Transport Planning ............................................................. 6

2.4 Stakeholder Consultation ........................................................................... 6

2.5 Long List of Projects .................................................................................. 6

Chapter 3.

Preparation Phase ............................................................................. 7

3.1

Project Preparation .................................................................................... 7

3.2

Prioritisation of Projects ............................................................................. 7

3.3 Technical Feasibility ................................................................................... 7

3.4

Environmental and Social Scoping ............................................................. 7

3.5 Economic Feasibility .................................................................................. 7

3.6 Financial Feasibility and Allocation of Funding ........................................... 7

3.7 Adjustment of Scope and Standards .......................................................... 7

3.8 Confirmation of Priority of Projects ............................................................. 7

Chapter 4.

Design Phase ..................................................................................... 8

4.1

General ...................................................................................................... 8

4.2 References ................................................................................................ 8

4.3

Preliminary and Detailed Design Stages .................................................... 8

4.4 Preliminary Design Stage ........................................................................... 8

4.4.1 Traffic Study and Prediction ............................................................... 9

4.4.2 Road Classification and Standards Determination .............................. 9

4.4.3 Route Determination ........................................................................ 10

4.4.4 Topographical Survey ...................................................................... 10

4.4.5 Geotechnical and Materials Survey .................................................. 11

4.4.6

Environmental and Social Impact Assessment ................................. 11

4.4.7

Resettlement and Compensation Plan ............................................. 11

4.4.8 Preliminary Geometric Design .......................................................... 11




Federal Ministry of Works ii

4.4.9 Preliminary Pavement and Material Design ...................................... 11

4.4.10 Preliminary Drainage Design ............................................................ 11

4.4.11 Preliminary Structural Design of Bridges and Culverts ..................... 12

4.4.12 Preliminary Design of Road Traffic Signs ......................................... 13

4.4.13 Identification of Affected Services .................................................... 13

4.4.14

Preliminary Design Report ............................................................... 14

4.5

Detailed Design ....................................................................................... 14

4.5.1 Preparatory Work ............................................................................. 14

4.5.2 Detailed Geometric Design .............................................................. 14

4.5.3 Detailed Drainage Design ................................................................ 15

4.5.5 Detailed Structural Design ................................................................ 16

4.5.6 Detailed Design of Road Traffic Signs .............................................. 17

4.5.7 Environmental Management Plan..................................................... 17

4.5.8 Resettlement and Compensation Plan ............................................. 17

4.6

Road Safety Audits .................................................................................. 17

4.6.1

Introduction ...................................................................................... 17

4.6.2

Definition of a Road Safety Audit ...................................................... 18

4.6.3 Objectives of a Road Safety Audit .................................................... 18

4.6.4 Key Requirements for Road Safety Audits ....................................... 19

4.6.5 Conducting Road Safety Audits ........................................................ 19

4.6.6 Road Safety Audit Report ................................................................. 22

Chapter 5. Implementation Phase ...................................................................... 24

5.1 Tender Process ....................................................................................... 24

5.1.1 Bid Document Preparation ............................................................... 24

5.1.2

Prequalification................................................................................. 25

5.1.3

Invitation and Submission of Tenders ............................................... 25

5.1.4 Adjudication and Award .................................................................... 26

5.2 Construction Contract .............................................................................. 28

5.3 Construction Supervision ......................................................................... 28

Chapter 6. Utilisation and Asset Management Phase ........................................ 30

6.1 Introduction .............................................................................................. 30

6.2 use of pavement management data for to assess road networkrequirements ........................................................................................................ 30

6.3 Operation of the Road .............................................................................. 31

6.4 Maintenance of Roads, Bridges, Signs .................................................... 31

Chapter 7. Annexes ........................................................................................... 31

7.1 Annex – Process to Appoint a Consultant ................................................ 31

7.2

List of Drawings for a Typical Designs ..................................................... 33

7.2.1

Highway Design ............................................................................... 33




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7.2.2 Typical List of Drawings for Bridges ................................................. 36

7.3 Annex – List of Typical Data Required for a Bridge Site ........................... 38

7.3.1 All Bridge Sites ................................................................................. 38

7.3.2 Additional Data for Grade Separations (Highway/Rail) ..................... 38

7.3.3 Additional Data for Grade Separations (Highway/Highway) .............. 39

7.3.4

Additional Data for Waterway Crossings .......................................... 39

7.4

Annex: Checklists for Road Safety Audits ................................................ 40

7.4.1 Preliminary Design Checklist ............................................................ 40

7.4.2 Detail Design Checklist .................................................................... 47

LIST OF FIGURES

Figure 1: Organisation of the Highway Manuals ........................................................................1

Figure 2: Flow chart showing the Phases of a Highway Project ................................................3

Figure 3: List of Processes in Phases ........................................................................................4

Figure 4: Process for Structural Design of Bridges ................................................................. 13




Federal Ministry of Works 1

CHAPTER 1. GENERAL INFORMATION

1.1 INTRODUCTION Road transportation is the life blood of any country’s economy in Africa and theFederal Republic of Nigeria is no exception. Nigeria has a well-defined network ofFederal Highways, into which numerous State and Municipal roads interlink toprovide a basis for road transportation access throughout the country. Freight andpassenger transport is able to move freely to support the growing economy of thecountry. Future development, maintenance and rehabilitation of roads generally, andthe Federal Highway network in particular, are key to unlocking the vast economicpotential of the country.

This Code of Procedure is aimed at identifying the key steps in the development andmanagement of roads and highways, to ensure that the system can meet the needs

of the country in an economically efficient, effective, safe and sustainable manner.The various phases of a road or highway project are listed and the importantelements that need to be taken into account in the process of developing,implementing, operating and maintaining that project, to give maximum economicbenefit to the country are indicated.

1.2 CODE OF PROCEDURE TO LINK TO HIGHWAY MANUALS

The Code of Procedure is the initial guide that links the user into the entire set ofVolumes of the Highway Manuals, as shown in Figure 1.

Figure 1: Organisation of the Highway Manuals

Volume I

Geometric Design

Volume II

Secondary Design Elements

Volume III

Pavement and Materials Design

Volume IV

Drainage Design

Volume V

Structural Design

Volume VI

Traffic Signs and Road Markings

Volume VII

Environmental Management

Part 1: Design

Volume I

Highway Inventory

Volume II

Maintenance Works

Volume III

Maintenance Costing

Part 2: Maintenance

Code of Procedure





1.3 DEFINITIONS

To assist in the clear understanding of the terminology used in this Code thefollowing terms are defined:

Agreement: The Contract Agreement entered into between the responsible

Authority and a Consultant.Consultant: A consulting firm or person appointed in terms of an Agreement.

Design Engineer: The departmental internal design engineer or a consulting firm orany other body (Consultant) who is appointed to do the designwork related to a road project.

Engineering Representative: The Engineer appointed by the Road Authority(normally in the employ of such Authority) for the supervision ofconstruction phase of a road project.

Project Engineer: The Engineer dealing with a road design project, on behalf ofRoad Authority (usually an employee of the Road Authority).

Resident Engineer: The Engineer appointed by the Road Authority (who can be anemployee of the Road Authority or a Consultant) to supervise theconstruction of the road project concerned.

Road Authority: In respect of a section of road, the Authority responsible for suchsection of road, this will be one of the following;

For Federal Highways - Federal Ministry of Works,

For State Roads – the Ministry of Works of the State inwhich the road is situated

For Local Roads – the Local Authority in which the

road is situated

1.4 PHASES OF A HIGHWAY PROJECT

The following are identified as the phases of a road or highway project:

Identification Phase

Preparation Phase

Design Phase

Implementation Phase

Maintenance and Operation Phase

Each of these phases comprises several processes that are illustrated in the flowdiagram in Figure 2 shown on the following page and listed in Figure 3. These arebriefly elaborated in the following chapters of this Code. The points within theseprocesses at which the various Volumes of the Highway Manuals need to bereferenced are identified, to facilitate uniformity of both procedure and technicalstandards used in developing highway projects.





Figure 2: Flow chart showing the Phases of a Highway Project

Construction ContractConstruction Supervision

HIGHWAY ENGINEERING: PHASES OF A HIGHWAY PROJECT

I d e n t i f i c a t i o

n P h a s e

D e s i g

n P h a s e

P r e l i m i n a r y D e s i g n S t a g e

Tender Process

Network monitoring

Land Use and Transport Planning

P r e p a r a t i o n P h a s e

Stakeholder consultation

Project

Prioritisation

Technical

Feasibility

Enviro &

Social

Scoping

Financial

Feasibility

Adjust Scope

and

Standards

Traffic Study .

Topo ,Geotech &

Materials Survey

Route

determin-

ation

Prelim Bridge

location &

design

Prelim Road &

Pavement

Design

Costs vs

budget

Detailed Design of Roads, Pavements, Materials,

Drainage & Bridges

Road Safety and Detailed Signs & Markings Design

EMP, RAP, Compensation plan, Sustainability

Production of tender documents & drawings

Production of Working Drawings

EIA, SIA,

Sustainability

D e t a i l e d D e s i g n S t a g e

Operation and Maintenance

I m p l e m

e n t a t i o n

P h a s e

U t i l i s a t i o n & A s s e t

M a n a g e m e n t

P h a s e

Network Monitoring

Economic

Feasibility





Figure 3: List of Processes in Phases

IDENTIFICATION PHASE

NETWORK MONITORING

LAND USE AND TRANSPORT PLANNING STAKEHOLDER CONSULTATION

LONG LIST OF PROJECTS

PREPARATION PHASE

PROJECT PRIORITISATION

TECHNICAL FEASIBILITY STUDIES

ENVIRONMENTAL AND SOCIAL SCOPING AND EVALUATION OF ALTERNATIVES

ECONOMIC ASSESSMENT

FINANCIAL ASSESSMENT AND ALLOCATION OF FUNDING

ADJUSTMENT OF SCOPE AND STANDARDS

DESIGN PHASE

PRELIMINARY DESIGN TRAFFIC STUDY AND PREDICTION ROUTE DETERMINATION TOPOGRAPHICAL SURVEY GEOTECHNICAL AND MATERIALS SURVEY BRIDGE LOCATION & CONCEPTS ROAD AND PAVEMENT DESIGN ROAD SAFETY ASSESSMENT ROAD SIGNS AND MARKING DESIGN ENVIRONMENTAL & SOCIAL IMPACT ASSESSMENT COSTS AND BUDGETS

DETAIL DESIGN OF ROADS, PAVEMENTS, MATERIALS, DRAINAGE &BRIDGES, ROADS SIGNS, ROAD MARKINGS, ROAD SAFETY,ENVIRONMENTAL MANAGEMENT PLAN (EMP), SOCIAL IMPACTMANAGEMENT PLAN (SIMP), RESETTLEMENT ACTION PLAN (RAP) &SUSTAINABILITY DESIGN

TENDER DOCUMENTATION

IMPLEMENTATION PHASE SIMP AND RAP IMPLEMENTATION

TENDER ADVERTISEMENT, BIDS EVALUATION, AWARD

CONSTRUCTION CONTRACT

CONSTRUCTION SUPERVISION AND EMP SUPERVISION

UTILISATION AND ASSET MANAGEMENT PHASE

OPERATION OF THE ROAD

MAINTENANCE OF ROADS, BRIDGES, SIGNS

NETWORK MONITORING (SERVICE QUALITY LEVELS – SPEEDS, RIDE,CAPACITY, STRENGTH, SAFETY, ENVIRONMENT & SUSTAINABILITY





1.5 RESPONSIBILITIES FOR HIGHWAY PROJECTS

Public roads in Nigeria are each allocated to one of three levels of Government.

Federal Highways are the responsibility of the Federal Government and are

planned and developed by the Federal Ministry of Works, and are maintained bythe Federal Road Maintenance Agency.

Roads, other than Federal Highways, within individual States and which are notLocal roads, are referred to as State roads and are the responsibility of the Statein which they are located.

Local roads lie within the Local Government areas, and fall under theresponsibility of the Local Authority for that area.

Roads built and maintained by private organisations, which are open to public use, mustalso comply with requirements for public roads and will fall under the State or LocalGovernment Authority (depending on their location) for the purposes of standards, eventhough they are privately funded.

The Authority responsible for a road will be generically referred to in this document as theRoad Authority or RA for the road concerned and may be any one of the above Authorities.

The Road Authority will need to take decisions relating to the various phases of theproject and manage the process, but the execution of the various tasks within theprocess can be done using the Road Authority’s own resources, by engaging consultingfirms to do planning, design, environmental and social impact assessment and technicalmanagement, and engaging contractors to provide specific services, equipment or theconstruction of facilities.

An outline of the process to engage a consultant is provided in the Annex in Section 7.1

of Chapter 7. The process of procuring contractors is briefly touched upon in Section __





CHAPTER 2. IDENTIFICATION PHASE

2.1 PROJECT IDENTIFICATION

The project identification phase for roads involves determining from among the followingprocesses or other sources, the need for road development and improvement. Thisphase is the responsibility of the Road Authority, which should be done within in thecontext of National, Regional and Local Planning for urban and rural development, ifsuch plans are available. Resources, in the form of consultants, can be drawn in by theRoad Authority for specific investigations and planning tasks, but the overall vision for theroad system remains the responsibility of the Road Authority. The procedure to appoint aconsultant, if required, is described in Annexure A

2.2 NETWORK MONITORING

Monitoring of the existing network of roads leads to the identification of rehabilitation andmaintenance needs, and capacity constraints that are inhibiting efficient transport underpresent demand. Such monitoring may in turn also entail an analysis of the balancebetween private and public transport supply and demand on the road network.

2.3 LAND USE AND TRANSPORT PLANNING

National and regional plans guide the future development of the country and thereforeprovide the basis for the future prediction of transport demand. The land use andtransport planning processes are interactive, as providing appropriate transport to andfrom developments can be a determining factor when the locations of mostdevelopments are decided upon. Road transport provision is a substantial aspect ofmeeting this transport demand to support the economy. Increasingly, environmentalissues are being included at the macro-planning level as an early warning or fatal flaw

identification mechanism when determining road network links at the regional scale.

2.4 STAKEHOLDER CONSULTATION

Formalised stakeholder consultation is provided for through the legislative and budgetaryprocesses established in Government, but these can be insensitive to needs in particularareas or under specific authorities. Where possible, consultation with key stakeholdersneeds to be conducted outside the formalized parliamentary process to both identifyneeds and to obtain “grass roots” support for proposed projects.

2.5 LONG LIST OF PROJECTS

The above processes can lead to a “long list of projects” covering new road provision and

specific road upgrading and maintenance needs.





CHAPTER 3. PREPARATION PHASE

3.1 PROJECT PREPARATION

The Road Authority ensures that projects identified are feasible in all respects and toobtain confirmation of priority ranking, more accurate costs for budget purposes and ofthe likely returns from the investment made in the projects listed. These are tasks whichare easily packaged for use of consultants.

3.2 PRIORITISATION OF PROJECTS

The long list of projects must be verified and prioritised on non-technical factors, toprovide the indication of which projects should be further investigated first.

3.3 TECHNICAL FEASIBILITY

The highest priorities of identified projects are then subjected to technical feasibility

studies to identify the technical parameters that will need to be addressed in undertakingsuch projects. Lengths of road and concept forms for major structures that will berequired are identified, as well as other major cost items that will be encountered inimplementing the project. Industry norms to determine costs should be used.

3.4 ENVIRONMENTAL AND SOCIAL SCOPING

Environmental scoping of potential impacts relating to identified road projects, includingthe evaluation of alternatives, needs to be carried out and social and sustainability issuesinvestigated. Costs relating to the mitigation of these identified impacts should also beestimated.

3.5 ECONOMIC FEASIBILITY

Using the costs determined for the project, and traffic estimates, high level economicfeasibility studies should then be undertaken to indicate investment needs and likelyreturns from such investment.

3.6 FINANCIAL FEASIBILITY AND ALLOCATION OF FUNDING

Financial analysis will determine the overall budgets as well as the timing of theinvestments that are required for the project. Funding for these projects must then beidentified and allocated.

3.7 ADJUSTMENT OF SCOPE AND STANDARDS

Where the costs of a proposed project either exceeds or does not reach the limit of fundsavailable for the project, the scope and standard of the project can be reviewed to createsavings or cost increases as appropriate.

3.8 CONFIRMATION OF PRIORITY OF PROJECTS

Economic returns (Net Present Value, Internal Rates of Return, Cost/Benefit Ratios) arethen used to provide confirmation/adjustment of the priorities among projects identified.

If required the entire project preparation process can be re-iterated to test alternatives ofscope and standard of a particular project, to determine the alternative with the highestbenefit cost ratio, or to fit available funding.





CHAPTER 4. DESIGN PHASE

4.1 GENERAL

As indicated in Chapter 1.5, a Road Authority may undertake road design using its owndesign resources or using a consultant. Where a consultant is appointed, the proceduralguideline to appoint the consultant, as shown in the Annex in Section 7.1 should be usedand adapted to the specific requirements of the project.

4.2 REFERENCES

In the execution of his duties outlined in this Code of Procedure, the Design Engineershall use the Highway Manuals Part 1: Design and reference the other technicalguidelines referred to in those Manuals.

4.3 PRELIMINARY AND DETAILED DESIGN STAGES

The steps in carrying out the design of a specific section of a highway are usuallyconducted in two stages, and the various tasks in each stage are listed here, and areclarified in the following subsections:

a) Preliminary Design Stage

o Traffic Study and Prediction

o Road Classification and Standard Determination

o Route Determination

o Topographical Survey

o Geotechnical and Materials Survey

o Geometric Design

o Pavement and Materials Design

o Environmental and Social Impact Assessment

o Resettlement and Compensation Plan

b) Detailed Design Stage

o Detailed Geometric Design

o Detailed Drainage Design

o Detailed Structural Design

c) Road Safety Audit

d) Bridge Location and Design

e) Environmental Management Plan

It should be noted that although the steps are presented sequentially, there will be aneed to iterate between two or more of these steps to determine the optimumarrangement for the project concerned.

4.4 PRELIMINARY DESIGN STAGE

Preliminary design is carried out to provide a technical solution to the design of theproject and to give an estimate of cost that will be within 20% of the actual finalconstruction cost. The preliminary design therefore provides a basis for interaction





between the Project Engineer and the Design Engineer, to allow the road standards andfacilities provided under the project to be adjusted to best achieve the objectives of theproject while remaining within available budgets.

4.4.1 Traffic Study and Prediction

General

Estimates of future traffic to use a road are required to determine the crosssections required along the road to accommodate the predicted traffic, and todetermine the strength of pavement of the road to carry the expected numbersof heavy vehicles that are anticipated during the life of the road.

Exist ing Traff ic

Where the project consists of upgrading of an existing road, an assessment ofexisting traffic should be made from:

Any available traffic count data.

A specific traffic count for the project, taken over as long a period aspossible. A minimum of a seven day classified count (classified as aminimum of 6 classes of vehicle – light vehicle, minibus, bus, heavyvehicle 2 axle, heavy vehicle 3-4 axle, heavy vehicle 5 axles and more)should be required. Where traffic data from a nearby permanent trafficcount station is available, the specific 7 day traffic count informationshould be adjusted according to the seasonal variations shown at thepermanent traffic count station, to better represent the annual averagedaily traffic on the project.

Traff ic Model l ing

Where the project road is a new road, anticipated traffic on completion of theroad needs to be determined based upon a traffic model taking account ofdiverted traffic and generated traffic. Traffic models can also be used to moreaccurately predict future traffic on existing roads.

Predicted Traff ic

Prediction of future traffic on the project road should be determined by at leastassessing planned future developments in land use as well as trends in generaleconomic growth in the areas served by the road.

Predictions of traffic (in the classes identified above) at the completion of the

project, and at points five, ten, fifteen and twenty years after the completion ofthe road should be made.

4.4.2 Road Classification and Standards Determination

The selection of the Class of Road and its function is to be determined fromChapter 2 of the Volume 1 – Geometric Design.





4.4.3 Route Determination

Purpos e of Route Determin at ion

The route determination is a process that is mainly required for new roads, butcan be required for existing roads where realignment is required on some

sections. The purpose of the route determination process is to:

establish the extent of the area to be covered by topographical survey toproduce site plans that will allow the detailed alignment to be selectedduring the preliminary and final design stages; and

produce a report which provides sufficient detail to form the basis forconsultation with Authorities and stakeholders.

Process for Prod ucing a Route Determinat ion

The steps to be followed include but need not be limited to the following:

a) Visual inspection of the site in order to determine physical controls.

b) Identifying preferred bridge sites for bridges across major rivers or forother required structures.

c) Acquisition and study of existing plans and aerial photographs.

d) Examine the Environmental and Social Impact Assessment Reportrelating to the project, or if this has not been completed previously, havesuch Report complied, and take into account the findings of such Report,particularly with regard to possible route alternatives.

e) Investigation of land utilization and development potential.

f) Liaison with Federal, State and Local Authorities, Utilities Service

Providers and other interested parties.

Required outputs o f Route Determinat ion

The Design Engineer shall compile a full report, including a key plan andinterpolated longitudinal sections, which shall comprehensively describe theproject and its objectives in non-technical terms and include:

A discussion of feasible or alternative routes.

A substantiated recommendation regarding the most suitable route,including cost estimates for the construction of alternative routes.

A listing of any important issues that will need to be investigated or

mitigated in the design process going forward.

4.4.4 Topographical Survey

The Design Engineer is responsible for all aspects of the survey work, which willusually be undertaken by a specialist survey contractor. The survey shouldinclude the basic ground survey, the establishment of permanent surveybeacons, the preparation of a digital terrain model in an appropriate electronicformat and the production of plans, including the compilation and plotting of alldata according to the relevant specification. This will include detailed sitesurveys for all major structures. Survey will be conducted in accordance with theHighway Manual Part 1 Design: Volume I Geometric Design.





4.4.5 Geotechnical and Materials Survey

The materials survey is to be carried out in accordance with the technicalguidance provided in the Highway Manual, Part 1: Design Volume III Pavementand Materials Design, and the standards and reference documents referred to inthat Volume of the Manuals.

Bridges site investigations require comprehensive foundation investigation,including drilling of cores to establish suitable founding levels for substructures,where required.

4.4.6 Environmental and Social Impact Assessment

A detailed Environmental and Social Impact Assessment will be required, as setout in the Highway Manual Part 1 Design: Volume VII Environmental and SocialImpact Management. An Environmental Management Plan, identifying impactsand mitigation measures, will be required for inclusion in the construction

contract documentation.

4.4.7 Resettlement and Compensation Plan

The exact areas of land that need to be acquired for the road project must bedetermined immediately the final alignment is decided upon. Land owners needto be identified, losses assessed and compensation for any land acquired mustbe determined, including relocation costs where appropriate.

4.4.8 Preliminary Geometric Design

The preliminary geometric design should include:

(a) Determining the most suitable horizontal alignment of the centre-line ofthe road.

(b) Provision of detailed route alignment for legal proclamation of the roadRight of Way (RoW) if this has not been done in the project preparationphase.

(c) The preparation of a recommended comprehensive vertical alignmentdesign for the roads, including interpolated longitudinal sections,preliminary planning with regard to the placing of road signs, and thepreparation of cross-sections from the Digital Terrain Model at intervalsnot greater than 40 m apart. Consideration of alternatives that cangenerate capital cost savings and the reasons why these are not

recommended shall be documented.

4.4.9 Preliminary Pavement and Material Design

(a) The estimation of the expected axle loading and the preparation of apreliminary pavement design.

(b) The investigation of the general geology of the area, the localoccurrence of road building materials and possible problem areas, thatmust be covered in full in the report.

4.4.10 Preliminary Drainage Design

Preliminary drainage design shall be produced to provide cost estimates within

20% of actual final costs. Design in accordance with the Highway Manuals Part1: Design Volume IV will be carried out for all watercourses crossed by the road,





to determine size and type of structure to be used and to allow the costing ofthese. In very flat areas, the Design Engineer should check that the preliminaryvertical alignment (Section 4.11.1) provides sufficient clearance for freelydischarging cross-drainage structures. If not, adjustment of the verticalalignment may be required. Costs for kerbing, channels, flumes, drain lining and

road surface drainage can be estimated at a per kilometre rate for thepreliminary design stage.

4.4.11 Preliminary Structural Design of Bridges and Culverts

General

All bridge structures and major culverts (span greater than 6m or skew or nonstandard culvert structures) shall be designed in accordance with the HighwayManual Part 1: Design Volume V Structural Design. The term “bridge” as usedin highway design applies to structures over waterways, grade separationstructures, road over rail structures and elevated highways. Each bridgepresents its own unique problems. The best type of bridge for grade separations

conforms to the highway alignment, profile, and cross section and gives driverslittle sense of restriction. The structure should be pleasing in appearance andproperly adapted to the site.

Locat ion of Br idges

Bridges are located to conform to the general alignment of the highway. Theideal location for a bridge crossing is one where:

The approach has a reasonable grade.

Soil and foundation conditions are adequate for the installation.

The need for future changes, such as widening, can be accommodated.

Economic considerations with regard to materials and constructionmethods can be optimised.

Safety of vehicular traffic and other road users is assured.

It may not always be possible to satisfy all of the abovementioned conditions butthey should all be carefully considered. When selecting new alignments for theroadway, careful consideration should be given to meeting as many of theseconditions as possible. The final decision for location should be based on acomplete analysis of the factors involved, including those relating to traffic

safety, operating conditions and economics.

Process for Prel iminary Brid ge Design

The iterative processes for balancing the various differing requirements for thedesign of a bridge are shown in Figure 4.





Figure 4: Process for Structural Design of Bridges

Requirements at Prel iminary Design Stage for Bridg es

For preliminary design a general arrangement showing the proposed layout andelevation of the structure is required, to allow the assessment of the proposedsolution and a preliminary costing of the structure. Locations of all structuresare to be shown on the road layout plans. A Bridge Schedule is to be preparedfor all new structures and for widening of existing structures.

4.4.12 Preliminary Design of Road Traffic Signs

The preliminary design must include the provision of traffic signs, traffic signals,and road markings. These can be a significant cost of the project particularly forhigh standard roads where gantries for mounting overhead signs, requiringlighting for visibility at night are required.

4.4.13 Identification of Affected Services

(a) The investigation of services that will be affected by the project, detailingof these on the drawings, and specifics of how these will be dealt withand the estimated costs thereof.

(b) A schedule together with plans showing all services, such as sewers,pipelines, cables, masts, irrigation canals, local accesses etc., as well asall RoWs, the Design Engineer's proposals as to how they are to beshifted and the estimated cost of relocation, as obtained from the service

authorities. This aspect must at least include inspection of properties for





services and interaction with Local and other Authorities and UtilitiesService Providers to identify affected services.

4.4.14 Preliminary Design Report

The compilation of a Preliminary Design Report is required containing detailed

contour survey plans showing the proposed design, a summary andrecommendations of the Environmental and Social Impact Assessment Report,a critical analysis of the route with clear motivation of proposals, together withdata on the standards which may be attained, as well as cost estimates. Otherissues that may be required as part of this report include:

(a) Any additional investigations should the route traverse mining land orundermined areas or areas subject to subsidence.

(b) Investigation and assessment of the impact of high order roads, railwaysand other important nodes on the project. Existing and future access torailway stations, airports and seaports and similar points of importancemust be addressed in all planning and design.

4.5 DETAILED DESIGN

4.5.1 Preparatory Work

In cases where a route determination report exists, but no approved preliminarydesign exists, the Design Engineer should undertake the following;

A visual inspection of the site, with special reference to materials andphysical controls which may influence the final alignment and route of theroad.

Study of the existing route determination report, small scale aerialphotographs and plans.

Liaison with public bodies, and other interested parties and investigationof land utilization and development potential.

Consult with the Project Engineer as to the extent of a preliminary designreport.

In cases where an approved preliminary design already exists, the DesignEngineer shall review the existing approved preliminary design critically beforeundertaking detailed design, and should she/he have any comments to make,such comments shall be submitted to the Project Engineer in writing.

4.5.2 Detailed Geometric Design

The Design Engineer ’s normal duties in respect of the Detail Design are asfollows

(a) The staking of the road, (usually by a survey contractor) together withthe taking of cross-sections and the carrying out of any additional sitesurveys required for the road or structures. Over relatively flat terraincross-sections shall be taken at intervals not exceeding 20 m, and overhilly or mountainous terrain at intervals less than 20 m as required.

(b) Preparation for moving of services: The Design Engineer shall liaise atan early stage of detailed design with all the owners of services affected





by the road, arrange for moving and make contractual arrangementtherefore.

(c) Prepare plans and detailed drawings, a full list of which, withrecommended scales, is provided in the Annex in Section 7.2

4.5.3 Detailed Drainage Design

General

The technical detail of design of storm water drainage systems is discussed inthe Highway Manual Part 1: Design - Volume IV: Drainage Design

Discussion in this Code of Procedure is therefore limited to policy andprocedures that the Design Engineer should incorporate in the cross-section toensure adequate drainage of the road reserve and the adjacent land. Adistinction is drawn between rural and urban drainage.

Rural drainage focuses on the safe removal of storm water from the

travelled way onto the verge and on its movement to a point where it canbe taken from the upstream to the downstream side of the road,ultimately discharging into a defined natural water course.

In an urban environment, the road reserve serves as the principalconduit of storm water from surrounding properties and its conveyance toa point where it can be discharged into natural watercourses.

In both rural and urban environments, storm water drainage is aimedboth at the safety of the road user and the protection of the integrity ofthe designed pavement layers of the road. The safety of the road userdictates that a maximum depth of an open drain be specified and therecommended maximum depth is 500 mm. The volume of water to be

conducted by a drain thus indicates the required width of the drain ratherthan its depth, since the need to protect the design layers from saturationby both storm water and subsurface water remains unchanged.

Drainage Design Proc edures

The fundamental principles of the procedure to be used in designing highwaydrainage are as follows:

Where natural water-courses and drainage channels exist the highwayshall be provided with appropriate cross drainage across these channelsor water courses, and the roadways and verge shall be drained directlyinto them.

Where conditions necessitate drainage beyond the limits of normalacquisition, more land shall be acquired for the necessary drainagechannels.

In urban areas where drainage channels have been provided by otherauthorities, a formal agreement relating to the extent of the amount ofdischarge from the highway shall be negotiated and entered into by theRoad Authority.

The Road Authority may participate in flood control projects in theinterest of the highway. The amount of participation shall be based onthe legal premise that aid must be restricted to the amount of benefit

accruing to the Federal Government by reason of the improvement. Suchprojects shall be covered by a formal agreement.





Design of cross drainage structures shall comprise the following steps:

Determination of a design flood by assessing catchment areas, rainfallintensity duration frequency, and selecting an acceptable return periodfor floods that will exceed the capacity of the proposed structure.

Selection of a structure providing capacity to accommodate the designflood.

A cross drainage schedule shall be compiled and included in the Design Report,which provides a list of catchment areas, return period selected, calculateddesign flood and capacity of structure provided.

Longitudinal drainage structures shall be designed to ensure flood waters aresafely carried to the point of natural discharge without excessive erosion orstagnation.

Road surface drainage should be designed to prevent unsafe flow depths (dueto the danger of aquaplaning) on the travelled lanes under design stormconditions, and adequate provision should be made to carry the accumulation ofthis water safely into the main drainage structures along and across the road.

4.5.5 Detailed Structural Design

General

Technical guidelines relating to the structural design of bridges and non-standard culverts is provided in the Highway Manual Part 1: Design - Volume V:Structural Design.

Bri dge Site Data

It is important to collect all the Bridge Site Data as it will have a major influenceon the ease of construction and construction costs. A list of typical informationrequired at a bridge site is shown in the Annex in Section 7.3.

Detai led Design o f Bridg es

The detailed design of the structures required for the road involves morerigorous application of the optimisation process illustrated in Figure 4, to obtainthe most efficient and effective structure, and to ensure that all loads are

adequately resisted. The design shall result in detailed drawings and schedules,a typical list of which is given in the Annex in Section 7.2.2Design Report

The design report shall contain investigations of the road project, with specialreference to the following:

Scope of Report.

Description of the route.

Traffic patterns (existing traffic counts, expected growth rate projections)and level of service to determine the number of lanes required or thenecessity of climbing lanes, as well as any other special characteristicregarding traffic.

Regional and urban development.





Geological and geographical factors.

Materials and pavement design.

Existing services and improvements affected.

Vertical and horizontal standards of alignment that are attained.

Detail of the structures designed

Detail of the drainage provided.

Design Calculations

A summary of environmental and social impacts and the environmentalmanagement and resettlement and compensation plans related to theproject, as well as any sustainability issues.

Detail of the results of the road safety audit and any special measurestaken to address safety issues.

Road signs and road marking Discussion on drainage

Traffic Accommodation

An estimate of construction costs and cash flow for the construction ofthe road

4.5.6 Detailed Design of Road Traffic Signs

Detailed designs for all road traffic signs, road markings, as well as full provisionfor traffic lights variable message signs, gantry mountings for overhead signsand the lighting thereof, must be detailed in both design drawings and in tenderdocumentation in the Bill of Engineering Measurements & Estimates (BEME).

4.5.7 Environmental Management Plan

The Environmental Management Plan (EMP) that is derived from the EIA mustbe full detailed and mitigation measures required must be specified in detail andincluded in the Bill of Engineering Measurements and Estimates, to ensure theprovision of these measures in priced in the

4.5.8 Resettlement and Compensation Plan

Normally the Resettlement and Compensation Plan for a project needs to beprepared in advance of the final tender documentation, because the need tofinalise land acquisition and compensation for affected persons has to becomplete prior to the commencement of construction.

4.6 ROAD SAFETY AUDITS

4.6.1 Introduction

Roads are designed with a large number of criteria in mind, including userconvenience, fuel economy, construction cost, environmental impact and otherplanning objectives. Safety is one of the criteria, but is often implicitly assumedto be achieved by adhering to prescribed standards of road alignment and

layout. Although these standards are derived with safety in mind, experience





shows that compromises are often made in the design process, resulting infeatures which have been the cause of road crashes and fatalities.

Road Authorities in several countries have developed road safety auditprocedures as a proactive measure to help prevent road crashes which resultfrom inadequate designs. These procedures are to be applied at different

stages in the design process, namely during the feasibility study, then after thepreliminary design and finally during the detailed design and preparation ofconstruction drawings. There are also road safety audit procedures for theconstruction stage as well as during the maintenance period of a road.

The choice of safety criteria is important in the design process and it is essentialfor the Design Engineer to have a good understanding of their origin. A designprepared by a Design Engineer who has a good understanding, not only of thecriteria, but also of their background and foundation, and who has applied thecommunity values, will probably create the desired level of service, safety andeconomy.

For many elements, a range of dimensions is possible and the Design Engineerhas the responsibility of choosing the appropriate value for a particularapplication. A Design Engineer with economy uppermost in mind may betempted to apply the minimum value, reasoning that, if the value is within theaccepted range, the design is "satisfactory". This may not always be the case.

The Design Engineer might find it appropriate to reduce values of design criteria,which is not necessarily a poor decision. The consequences need to bethoroughly understood, particularly as they impact on safety and on costs andbenefits. Ameliorating measures, such as the use of traffic control devices, mayneed to be considered in the design process. If a design involves compromise, itmay be more appropriate to vary several elements by a small amount than toalter one element excessively.

The design of a road is a trade-off between standards and the cost of providingthem. The cost to society of road crashes and deaths often exceeds the totalannual expenditure on roads. Reducing initial construction costs of roadprojects can result in increased life cycle costs if the cost of accidents, injuriesand deaths is included in the economic calculations. It is the design engineer'sresponsibility to inform the client of the consequences of inadequate expenditureon safety.

It is often difficult and expensive, to correct safety defects at a later stage. Forthis reason, designing for safety should occur during the design process, and beprovided for in preparation of construction drawings.

Road safety audits on the design should be carried out by an independentperson who is not part of the design team.

4.6.2 Definition of a Road Safety Audit

A Road Safety Audit is a formal examination of a proposed (designed) orexisting road in which an independent, qualified examination team or personreports on the accident potential and safety problems of the road and suggestsmeasures to mitigate these problems.

4.6.3 Objectives of a Road Safety Audit

The objectives of a Road Safety Audit are:





To identify and report on the accident potential and safety problems of aroad during the design, construction or operating stages.

To ensure that road elements with an accident potential are removed orthat measures are implemented to reduce the accident risk thereof.

To minimise the severity and risk of road traffic accidents that may beinfluenced by the road facility or adjacent environment

To minimise the need for remedial measures after the opening of a newroad

To reduce the full life-cycle cost of a road project by reducing its accidentcost

To create and maintain an awareness of safe design practice during allthe stages of a road project.

4.6.4 Key Requirements for Road Safety AuditsThe following aspects are key requirements for successful Road Safety Audits:

Adequate time and information to conduct the road safety audit.

Commitment from the Road Authority

A recognised and agreed Road Safety Audit process

An independent road safety audit team or auditor

Checklists for the various stages of a road project

Evaluation and monitoring of the Road Safety Audit Process.

Adequate time should be provided during the process to allow for:

The scrutiny and evaluation of safety related aspects of all drawings andrelated project documents

The collection of any additional information required to carry out theRoad Safety Audit

The preparation of a formal Road Safety Audit Report.

4.6.5 Conducting Road Safety Audits

The greatest potential to improve road safety is in the pre-construction phase ofa project when the design of a project can be positively influenced Pre-

construction phase audits can be conducted on any proposal that is likely toinfluence the interactions between road users, or between road users and theirphysical environment.

During the design process, road safety audits are required at two stages,namely after preliminary design and again after detailed design, prior toconstruction drawings being issued for implementation.

Check lists for conducting these two road safety audits are included in the Annex in Section 7.4.





Prel iminary Design Safety A udit

The Preliminary Design Road Safety Audit is done after completion of a draftdesign. If alternative schemes have been developed, each scheme should be

audited.

A Preliminary Design Stage Road Safety Audit has the following objectives:

To address the design standards utilised for the draft design;

To consider, among others, the following:

o Alignment (horizontal, vertical);

o Sight distances;

o Layout of intersections and configuration of interchanges;

o Widths: Lanes and shoulders;

o Cross-section and super elevation of pavement;

o Location of accesses;

o Provision for different road user groups: Pedestrians, Cyclists,Heavy vehicles, etc

To evaluate whether any deviation from guidelines and design standardswould impact safety negatively;

To determine how possible staged implementation of the project could

influence road safety; If staging is proposed then the safety of eachstage should be considered as well as the transition from one stage tothe next;

To evaluate the possible departures from standards and the effectthereof from a safety perspective;

To evaluate that all road user groups have been considered, such as:

o Can vehicles turn safely?

o Can road users see each other?

o Can road users see traffic control devices?

o Is cross-section and alignment appropriate?o Is property access safely catered for?

To evaluate intersection layouts for possible conflict points;

To alert Design Engineers to areas where attention on road safetyaspects will be needed during the detail design stage;

To evaluate safety at the connections with existing roads, e.g.:

o Consistency

o Vulnerability of fixed objects, etc

In a Preliminary Design stage audit, the road safety audit team shall visit the siteof the proposed project taking special cognisance of the following:





Locations that involve permanent changes to the existing road layout orfeatures;

Transition areas between existing roads and the proposed projects.

At this stage of the design process fundamental decisions regarding route

choice, the overall design and layout of the project have already been decided.The audit team may still suggest physical changes to horizontal or verticalalignment, provision of a median, lane and shoulder width, provision of cyclelanes or sidewalks or channelisation. Accesses provided should be reviewed forupstream and downstream effects, possible conflicting movements, sightdistance and the possible consolidation of access points. Any suchrecommendations should be based on the consideration of safety issues onlyand should be supported by justifiable background reasoning, which need notnecessarily be included in the road safety audit report.

The ability of the design to safely accommodate future widening, expansion orextension should also be taken into account. Specific attention needs to begiven to assess the safety of different usage scenarios.

Detai led Design Safety Aud it

The Detailed Design Road Safety Audit normally takes place after completion ofthe detailed design but before the contract documents are prepared. This stageis the last opportunity to influence the design before construction commencesand is a review of those drawings that are put forward as those on which theproject will be constructed. This audit is very much focused on aspects of detailof the road layout, traffic arrangements and information transfer to the proposedroad user groups. It is also important that any issues that have not beensatisfactorily been resolved from earlier audits be reiterated in this. It may wellhappen that the proposed remedial measures for such an outstanding issue be

different in this stage than an earlier stage, because the flexibility to influencethe design is less.

A Detailed Design Road Safety Audit has the following objectives:

To consider, among others, the following:

o Any changes since the Preliminary Design Audit;

o Road traffic signs and markings;

o Road lighting;

o Intersection detail;

o Roadside hazard management issues (clear zones, trafficbarriers, fixed objects etc.)

o Needs and requirements for Special Road Users (pedestrians,cyclists, individuals with disabilities, heavy vehicles, buses etc.)

o Traffic management and control drawings for the proposedaccommodation of traffic during construction

o Drainage

o Landscaping

o Cross-section and side-slopes, etc.





To review those findings of the Preliminary Design Audit and theimplementation of mitigating measures;

To identify anything missed in the previous audit and confirm themitigating measures that may have been implemented as a result ofearlier findings;

To utilise the last opportunity of influencing safety prior to theconstruction of the project;

To evaluate the possible departures from standards and the effectthereof from a safety perspective;

To review the safety of typical details to be used on the project;

To evaluate the signage, markings and landscape plans;

To evaluate that all road user groups have been considered, such as:

o Can vehicles turn safely?

o Can road users see each other?

o Can road users see traffic control devices?

o Is cross-section and alignment appropriate?

o Are fixed hazards located within the relevant clear zone?

To review the interaction of the detailed elements;

To evaluate safety at the connections with existing roads, especiallyconsistency;

In the detail design stage audit, the road safety audit team shall visit the site ofthe proposed project taking special cognisance of the following:

Locations that involve permanent changes to the existing road layout orfeatures;

Transition areas between existing roads and the proposed projects.

At this stage the drawings should be completed to such a stage that they couldbe used in the preparation of contract documentation. If the audit team areconcerned about a possible lack of sufficient details, the audit team may requestsuch additional details from the client or project manager to allow the audit to becompleted without possible conditional findings. If the project will beimplemented in separate stages, each stage should be considered as well asthe transition between stages. This is specifically also applicable for the

proposed traffic management for the accommodation of traffic duringconstruction.

4.6.6 Road Safety Audit Report

A road safety audit report shall include the following:

A brief description of the audited project;

Identification of the audit stage and the team members as well as thenames and affiliation of other contributors to the audit;

Details of who was present at the site visit/s, when it was undertaken andwhat the conditions were on the day of the visit (weather, traffic, etc.)





The specific road safety problems identified, supported with thebackground reasoning, stating:

o The location of the problem;

o The nature of the problem;

o The type of crash that is likely to occur as a result of the problem;

Recommendations for action to mitigate or remove the problems, takingcognisance that:

o The recommended remedial measure shall be appropriate andviable for that particular stage of the audit;

o Recommendations should be proportionate to the scale of theidentified problem;

o Recommendations worded as “to consider...”, “to study....”, “tomonitor...”, “to investigate possible treatments and implement themost appropriate...”, etc. shall be avoided;

o Recommendations shall not be motivated for implementation in away that could be construed as the audit team trying to convincethe client to take a specific action.

An A3 or A4 location map, marked up and referenced to the problemsand, where available, photographs of the problems identified;

A statement, signed by the audit team leader in the recommendedformat;

A list of the documents and drawings considered for the audit.

The Audit Team shall send a draft report directly to the client representative.The Audit Team Leader shall discuss the draft report with the clientrepresentative prior to formal submission. The purpose of this discussion issolely to ensure that the findings and recommendations are within the scope ofthe audit, as defined in the audit brief. The client representative shall refrainfrom requesting amendments to the findings or the recommendations. Once theRoad Safety Audit Report is issued, it is a FINAL report – the report can not beamended and the Client may not request amendments or ask team members toomit certain details or findings.





CHAPTER 5. IMPLEMENTATION PHASE

5.1 TENDER PROCESS

5.1.1 Bid Document Preparation

Engineering Plans & Drawing s

A full set of design/construction plans is to be generated providing sufficientinformation for prospective Contractors to bid/tender and subsequently constructthe Works, should the bid be successful.

Bil l of En gineering Measurements & Estimates (BEME) & Preambles

The BEME shall be compiled and sequentially refined/amended consistent withthe engineering designs and construction plans prepared. The schedule ofquantities shall be priced by the Design Engineer to produce an accurate costestimate that shall be maintained as strictly confidential. The cost estimate willbe reviewed/revised in light of the general state of the local road constructionindustry.

Works Specif icat ions

The specification of the Works shall refer to the General Specifications (Roadand Bridges) of the Federal Ministry of Works1. Specifications of particularapplication must be compiled where the General Specifications do notadequately cover the work to be carried out on any part of the project.

Tender Docum ents

Draft tender/bidding documents are to be compiled and shall contain thefollowing:

Form of Tender and concise instructions to tenderers on preparation oftenders;

The General Conditions of Contract used by the Road Authority;

Special Conditions applying to the project

Specifications of particular application to the standard specifications forRoad and Bridge Works generally used by the Road Authority;

Specifications of particular application to cover the requirements of theenvironmental mitigation plan;

Specifications of particular application to cover the requirements of theHIV/AIDs awareness and prevention campaigns;

Specifications of particular application to cover local labour and sub-contracting requirements;

Description of the project including overall objectives and summary ofworks;

Materials/geotechnical information;

1 Government of the Federal Republic of Nigeria, General Specification (Roads and Bridges),

Revised 1997





Full set of construction plans;

Schedules of quantities.

Where prepared by Consultants, draft tender/bidding documents together withthe detailed design report shall be submitted/presented to the Road Authority for

review and comment.

5.1.2 Prequalification

A pre-qualification process may be required to select competent tenderers.Clauses shall be compiled and inserted in the Bidding Data section of thebid/tender documents to cover the qualification requirements for bidding.

The pre-qualification dossier or bidding document shall give a description of thescope of the envisaged project and request prospective Contractors to presentdetails regarding:

Eligibility to Bid;

Experience in similar “Works” contracts regionally;

Specific work experience in country;

Work commitments at time of pre-qualification submission;

Availability and ownership of basic construction equipment;

Financial standing and results of the past five (5) years;

Contact details of Clients and financial references;

Joint Venture arrangements, if any;

Extent of “local” involvement in project;

Anticipated scope of subcontracting;

Policy procedures and statement regarding health and safety.

In the case of a proposed Joint Venture, each party shall provide separateinformation and the submission will need to also provide details of theanticipated level of involvement of each party.

5.1.3 Invitation and Submission of Tenders

Tender Invi tat ion includin g Adm inistrat ion Duties

The tender invitation process shall be conducted by the Road Authority, or shallbe carried out by the Consultant appointed for the project, in close consultationwith the Road Authority at all stages, and shall include the following:

Compile list of approved contractors

Advertise in selected publications

Invite tenderers to collect documents

Keep audit record of tender deposits and a list of organisations collectingdocuments

Organise the pre-bid meeting and site inspection, if required

Arrange clarification meetings, if required





Prepare replies to queries

Prepare addenda to tender documents

Ensure that all potential bidders receive all tender information issued

Site Visi t and Pre-bid Meeting, Minutes and Report

Where required a site visit and pre-bid meeting shall be arranged for alltenderers to ensure that they acquaint themselves with the local conditions,environment and type of materials available, thereby eliminating some of therisks and consequent inflated cost. It shall also enable contractors to assess theavailability of aggregates.

Any queries related to designs, documentation and drawings shall be clarifiedduring the site visit and meeting, in the presence of all potential tenderers, theDesign Engineer and Roads Authority representatives.

The site visit and meeting shall be recorded and issued as minutes. Responsesto queries and clarifications, supplemented by the Design Engineer's comments,and decisions by the Road Authority, will be issued as an addendum, to becomepart of the Contract.

Tender Clari f icat ions, Addend ums, Closing Date

On a day to day basis throughout the tender period, queries from tenderers’ maybe received. These shall be monitored by the Design Engineer and clarified inclose consultation with Roads Authority.

If necessary, addenda shall be prepared and issued by following the prescribedprocedure, ensuring receipt and acknowledgement by each tenderer prior to the

closing date.

5.1.4 Adjudication and Award

Computer aided evaluation of tenders shall be based on the following principlesteps:

a) Technical matters

(i) Conformity with specification and drawings

(ii) Conformity to time constraints, if applicable(iii) Identification of alternatives

(iv) Methods of construction and temporary work

(v) Preliminary programme

(vi) Work to be sub-contracted

(vii) Adequacy of proposed construction plan and equipment

(viii) Adequacy of management structure

(ix) Financial matters

(x) Arithmetical accuracy(xi) Reasonableness/conformity to limited establishment cost





(xii) Reasonableness of unit rates

(xiii) Reasonableness of time related costs

(xiv) Reasonableness of lump sums

(xv) Reasonableness of profit margins on labour and plant

(xvi) Reasonableness of transportation and fuel costs

(xvii) Scheduling of payments (cash flow versus progress)

(xviii) Discounted cash flow and net present worth

(xix) Currency payment requirements

(xx) Contract price adjustment

(xxi) Conformity of bonds and guaranteesb) General Contractual Obligationsc) Conformity with instructions to tenderersd) Completeness of tenders

e) Validity of tendersf) Exclusions and qualifications, whether stated or impliedg) Adequacy of insurancesh) Working hour/public holidayi) Labour resources j) Administration expertise

The benefits to the Road Authority resulting from alternative designs shall beevaluated and the practicality of alternatives shall be investigated.

Proposed design alternatives shall be checked from an engineering point of viewand cost of design changes shall be extracted if applicable.

An evaluation system for alternative designs by various tenderers shall bedeveloped if necessary to apply fair and professional criteria to the overallevaluation of tenders submitted.

The evaluation process shall also include a sensitivity/risk analysis of keyaspects of the tenders, including the following:

Variance of main quantities and their effect on the overall tender price

Optimistic production rates

Failure to meet programme completion dates

The evaluation results shall be presented in the draft Tender Evaluation Report.

All priced items, mark-ups and alternatives shall be tabulated to becomecomparable with the original Design Engineer ’s estimate.

The objective of this final task in the evaluation process is to arrive at a fairevaluation of all tenders received, including any alternative offers.

Fully motivated, definite recommendations for the award of tenders shall beincluded in the draft Tender Evaluation Report. This will includerecommendations for any conditions, which may need to be imposed on thepreferred bidder.

The draft Tender Evaluation Report shall be considered by the Road Authority,and following receipt of comments and after due consultation, the final tenderevaluation report will be prepared and submitted for approval by the authorisedmember of the Road Authority.





Once the Tender Evaluation Report is approved the preferred bidder will beawarded the Contract.

5.2 CONSTRUCTION CONTRACT

The Road Authority shall then enter into the contract with the preferred bidder to carry

out the works according to the contract document.

5.3 CONSTRUCTION SUPERVISION

The Roads Authority will appoint a suitably qualified person or a consultant as “theResident Engineer” for supervision of the construction of the project and to monitor thedefects liability maintenance period.

The Engineer shall be responsible for proper supervision of the execution, of the work,including the checking and approval of any later alternative designs, designs fortemporary works, construction details (such as pre-stressing details) submitted by theContractor, and of workshop details in the case of the structural steelwork according tothe Contractor's working drawings and construction methods.

If deemed necessary an environmental specialist shall be appointed for the constructionphase, to monitor the implementation of the Environmental Management Plan. Thisshould preferably be from an independent environmental firm.

Typical supervisory staff shall be provided in the categories below in respect of eachcontract for which a tender is accepted:

(a) The Resident Engineer shall be properly qualified and experienced in thetype of work to be supervised, and must be a COREN RegisteredProfessional Engineer.

Approval for the appointment of the Resident Engineer shall be obtainedfrom the Roads Authority.

(b) A properly trained Materials Engineer or Technician who can perform andinterpret all material tests as stipulated in the specifications, to exercisecontrol over material quality, compacting and finishing. The Engineer orTechnician must be registered. The appointment of the Materials Engineeror Technician shall be approved by the relevant Roads Authority.

(c) A properly trained surveyor who can interpret all survey and setting-outplans, survey manuals, cadastral data, quantities, etc. The surveyor mustbe registered as a Surveyor. The Engineer shall, in accordance with theHighway Design Manuals, liaise with the relevant Road Authority andauthorize all design changes.

(d) All design changes must be finalized by the Resident Engineer and theEngineer Representative of the relevant Roads Authority.

The Resident Engineer and his representatives on site during the construction phase areresponsible to the Roads Authority to “administer the contract” as stipulated in theGeneral Conditions of Contract.

Under no circumstances are changes in the design to be authorized on site withoutconsultation with the Resident Engineer and the Engineer Representative of the Road Authority.

The Resident Engineer shall make recommendations to the Road Authority regarding thenumber of supervisory staff required, taking into account the extent of the contract and

the Contractor's rate of progress. .





The Resident Engineer is responsible for the administration of the contract, including thecertification of all payments, the provision of monthly progress reports and a list of workrejected, as well as a three monthly report reflecting the financial state of the contract,which takes into account the incomplete work and negotiations with the Contractor inconnection with matters arising from the contract.

The Resident Engineer is responsible for the execution of any duties assigned to him orher in terms of the general and special contract conditions applicable to the project.

The Resident Engineer is responsible for regular site visits to ensure the properexecution of the contract.

After completion of the contract, the Resident Engineer shall submit to the Roads Authority all construction details, “As Built” completion plans and materials test results.

Any changes/omissions/issues relating to environmental matters shall only be addressedas stipulated in the Environmental Management Plan and Environmental and SocialImpact Assessment Report, and only after advice from the appointed environmentalspecialist and consultation with and approval from the Roads and Environmental

Authorities.In the case of archaeological or paleontological findings during construction, theconstruction work in the area of the findings shall be stopped and the Roads Authorityand other applicable heritage Authorities shall be notified immediately.





CHAPTER 6. UTILISATION AND ASSET MANAGEMENTPHASE

6.1 INTRODUCTION

To extend the lifespan of roads within Nigeria and to provide and retain theroad network to an acceptable standard, and thereby contain travel time andvehicle operating costs within reasonable limits, it is imperative that appropriatemaintenance procedures be adopted.

Maintenance methods are detailed in Highway Manual Part 2, which providesmaintenance personnel information in making logical decisions for application ofacceptable maintenance methods for maintenance of over 34,000 kilometres of

road network within the Nigeria. The guidelines provide an easy proceduralreference book on all aspects of work required in the maintenance and repair ofroads, be it by direct labour or by contract.

In addition to maintenance methods and procedures, this manual also coversthe following:

Pavement distress identification,

Pavement management information,

Road user and worker safety procedures

6.2 USE OF PAVEMENT MANAGEMENT DATA FOR TO ASSESS ROAD NETWORK

REQUIREMENTS

To manage a road network information is required on the condition of the roads inthe network. This information is obtained from gathered data and it is essential aPavement Management System is available to record the data.

At network level information related to the condition of the entire network isrequired for policy and programming decisions. Network – level pavementmanagement data is extracted from PMS information and used to derive the

following information:

Identify and prioritise projects;

Establish rehabilitation programmes

Estimate overall short- and long-term needs

Establish budgetary requirements for major and maintenance works

Pavement management at project level provides detailed and technicalinformation related to a specific road section or sections.

Project – level pavement management data is extracted from PMS information





and used to derive the following information

:

Details of the road pavement structure

Condition of the road section

Determine repair or maintenance requirements for the specific road section orsections

Cost estimates and planning

Feedback and the documenting of actions taken

Additional information to be collected and documented to form part of the PMSdata base, includes the following:

Geometric data of the pavement such as length,width.

. Pavement structures and layer thickness

Present Serviceability Index (PSI) of the pavement

International Roughness Index (IRI) of thepavement

Road skid resistance

Accident records

Maintenance and construction data

Weather data.

6.3 OPERATION OF THE ROAD

6.4 MAINTENANCE OF ROADS, BRIDGES, SIGNS

CHAPTER 7. ANNEXES

7.1 ANNEX – PROCESS TO APPOINT A CONSULTANT

Where a consultant is required to assist with technical aspects of developing a project, awritten agreement between the Road Authority and the consultant will be entered into

comprising a minimum of a detailed terms of reference defining clearly the deliverables to





be produced and a schedule of payments for the services, tied to specific milestones andproduction of the deliverables identified.

To identify suitable consultants, and to ensure optimal use of the Road Authority’s funds,public procurement processes as defined either by the Federal or State Government willbe followed. These processes will consist of some or all of the following steps:

Advertising for suitably qualified consultants to express interest in providingservice required. This advert must describe the services required as fully aspossible, and indicate the basis upon which a short list of candidates will becompiled, preferably giving guidance on information to be submitted forassessment. A deadline for submission of expressions of interest must be stated.

After the closing date, submitted expressions of interest shall be assessed uponthe basis of the suitability of experience of the firm together with the qualificationsof the staff that are available within the firm. Formal scoring of each submissionto provide a record of the reasons for the selection of certain bids to be shortlisted is required, as there will usually be queries as to why one firm ofconsultants is short listed while another is not. A formal scoring system dispelsarguments during this phase.

The Road Authority will then prepare a Request for Proposals (RFP), whichcontains instructions to the bidders, a detailed terms of reference providing background to the project, detailed requirements, a clear definition of the deliverablesrequired, and the programme for the services, as well as the format for thesubmission of bids (which is designed to make comparison of submissions easierto carry out). The terms of reference later form part of the agreement asmentioned above. The RFP may require submission of technical and financialproposals, or in specific circumstances only technical or only financial proposalsmay be required.

Shortlisted consultants will then be issued with the RFP document and are invitedto submit bids by a specific date.

Consultants can then prepare bids based on the RFP and submit these by thespecified date. Late submissions are usually disqualified, to prevent anyundermining of the system.

Adjudication of bids submitted is then carried out. Again formal recorded scoringis recommended, usually using the members of a procurement or tendercommittee to each score the proposals submitted, to obtain an average balancedassessment of the bids. All submissions that obtain better then a minimum score(usually 70% minimum) are then eligible to be considered for appointment.

If technical and financial bids were requested, the consultants who submittedtechnical bids passing the minimum technical score will be invited to a publicopening of financial ***bids. The technical scores of each bid together withamount of their financial bid is then read out at the meeting. Financial bids and

technical scores are then both taken into account to identify the preferred bidder.If the RFP requested technical bids without financial considerations then theconsultant offering the bid with the highest technical score is identified as thepreferred bidder.

The preferred bidder is then invited to negotiate the contract, at which meetingany clarification and confirmation of information in the bid is obtained. This willinclude the confirmation that the staff listed in the proposal are available andready to carry out the project as proposed. The programme for the project is alsoconfirmed.

A formal consultancy contract is then signed to get the project underway.





7.2 LIST OF DRAWINGS FOR A T YPICAL DESIGNS

7.2.1 Highway Design

Main list of road plans:

(e) Key plan (1:5,000 or 1:10,000)(f) Layout plans (1:1 000)

(g) Setting out plans (1:200 or 1:500 or 1:1,000)

(h) Longitudinal sections (1:1,000H, 1:100V)

(i) Typical cross-sections (1:100H and 1:50V)

(j) Detail cross-sections (Every 20 m) (1:200)

(k) Relocation of service plans (1:1,000)

(l) Shifting of services schedule

(m) Contour plans of intersections and interchanges (1:200 to 1:500)(n) Road signs and markings (1:200 to 1:500)

(o) All necessary typical plans

Key plans to a scale of 1:5,000 or 1:10,000 to show the following details :

(i) Centre line for dual carriageways and freeways

(ii) Road reserve

(iii) Bridges and interchanges

(iv) Road numbers and/or street names(v) Destinations

(vi) Existing roads and public or access roads

(vii) Roads to be closed or deviated

(viii) Kilometre distances (km)

(ix) Subdivision of properties and farm names

(x) Cadastral boundaries

(xi) Rivers and their names

(xii) Railway lines(xiii) Radii of horizontal curves (m)

(xiv) Limits of construction

(xv) Borrow areas, materials sources and quarries, water abstractionpoints and possible access roads to these

(xvi) Position of layout plans with their numbers.

(xvii) Complete list of the detailed design plans with the number of eachplan (Plan No. followed by description). If the plan index is compiledon a separate plan, this plan must be allocated a separate key plannumber.

(xviii) North point





(xix) Drawing scale, bar scale with legend and units

(xx) Locality sketch to a suitable scale (1:250,000) to indicate the roadbeing planned in relation to towns, well known places, and otherroads, and must indicate town or place names.

Layout plans of the road and all cross-roads on detailed contour surveys to ascale of 1:1 000, showing the following details:

(i) Proposed route

(ii) Bridges and interchanges

(iii) Road numbers and/or street names

(iv) Destinations

(v) Existing roads, streets and service roads

(vi) Roads to be closed or deviated

(vii) Kilometre distances (km) (every 200 m)

(viii) Radii of horizontal curves (m)

(ix) Tabulated values of horizontal curves : Radius, length, deflectionangle, tangent length, transition lengths

(x) Positions of points of intersection and coordinate values (PI’s).

(xi) Beginnings and ends of horizontal curves and co-ordinate values

(xii) Distance between carriageways (for dual carriageways and freeways)

(xiii) Travelled way and shoulder widths (shaded on tarred portions only)

(xiv) Road reserve widths

(xv) Road reserve boundaries

(xvi) Directions of traffic movement

(xvii) Extent of cuts and fills (unless this is indicated on separate plans)

(xviii) Guardrails

(xix) Culverts with sizes, skew + km distance, drainpipes, mitre banks,catch water berms and flow directions with a suitable legend ofsymbols used

(xx) Catch pits

(xxi) Intersections and accesses

(xxii) Angles of intersections

(xxiii) Existing bridges and their numbers

(xxiv) New bridge numbers

(xxv) Co-ordinates of reference points to the nearest 0,01 m (singlecarriageways only) (BC, EC, PI)

(xxvi) Limits of construction

(xxvii) North point

(xxviii) Drawing scale and bar scale with legend and units





(xxix) Sheet No. of total number of sheets (sheet no 1 of 3)

(xxx) Plan numbers of adjacent sheets.

Longitudinal sections to a horizontal scale of 1:1,000 and vertical scale of 1:100,

of the road, cross-roads, access roads and ramps shall show the followingdetails:

(i) Positions of pegs and reference pegs with their elevations

(ii) Elevation of staked ground line (for dual carriageways and freeways)

(iii) Bridge and interchange positions and their numbers

(iv) Destinations

(v) Kilometre distances (km)

(vi) Datum level

(vii) Gradients (%)(viii) Lengths of vertical curves

(ix) K-values

(x) Vertical points of intersection and their elevations (PI’s)

(xi) Beginnings and ends of vertical curves

(xii) Beginnings, ends and other details of horizontal curves

(xiii) Details of super-elevation (e-value and edge levels)

(xiv) Reduced ground levels on the road centreline to the nearest 0,001 m

(xv) Reduced ground levels on the staked line to the nearest 0,001 metre(dual carriageways and freeways)

(xvi) Road levels on the centre line to the nearest 0,001 metre (for singlecarriageways)

(xvii) Road levels on the left and right edges and the centre of the travelledway to the nearest 0,001m (for dual carriageways and freeways)

(xviii) Setting-out details (at the top of the longitudinal section for singlecarriageways)

(xix) Design speed of all roads; positions of intersecting roads and otherreference points

(xx) Positions of interchanges, ramp noses, intersections and accesspoints (includes farm accesses) with the actual sight distances in alldirections up to 500 metres. Thereafter, only indicate "exceeds 500m"or > 500m. (In the case of ramp noses, the sight distance, ismeasured to a point on the road surface at the ramp nose)

(xxi) Culverts and drainpipes; km distance, sizes and skew

(xxii) Guardrail

(xxiii) Surfaced shoulders

(xxiv) Barrier lines (for single carriageways)

(xxv) Kerbing





(xxvi) Earthworks quantities for each section of cut and fill for singlecarriageways

(xxvii) Drawing scale and bar scale (horizontal and vertical).

Typical cross-sections to a suitable scale that show the following information:

(i) Centre line of the road

(ii) Distance between carriageways (dual carriageways and freeways)

(iii) Median widths (dual carriageways and freeways)

(iv) Side slopes

(v) Side drains

(vi) Reserve width

(vii) Formation width

(viii) Lane and shoulder widths

(ix) Kerb widths

(x) All dimensions

(xi) Clearances

(xii) Crossfall (%) of roadway and shoulders

(xiii) Subsurface drains

(xiv) Drawing scale and bar scale with units and legend

(xv) Any other details as on the Departmental type plans

7.2.2 Typical List of Drawings for Bridges

Main list of drawings required:

(a) Site Plan:

(i) Key plan

(ii) Locality plan

(iii) List of drawings

Is a separate site plan required for another Authority (for example the Railway

Authority)? Has such site plan been submitted to this Authority for approval?(b) General arrangement drawing containing:

General notes

Elevation of the bridge

Longitudinal section through the bridge

Plan of the bridge

Cross-section of deck

(c) Foundation plan(s)

(d) Working drawings includingConcrete drawings





Reinforcing drawings

Pre-stressing detail (where appropriate)

Balustrade detail

Miscellaneous drawings

(e) Steel bending schedules

(f) Standard plans numbered with the bridge number and sheet number

(g) Confirm that the latest drawing sheet template is being used?





7.3 ANNEX – LIST OF T YPICAL DATA REQUIRED FOR A BRIDGE SITE

7.3.1 All Bridge Sites

The following field data should be collected for all structures:

Location of any sewers, telephone and telegraph lines, water lines, gaslines, masts, culverts and location of other existing structures

Alignment of the proposed improvement and any traffic canalisation orseparations in the vicinity that would affect the structure.

Location of existing right of way lines and any intersecting highway orrailway, and the position of the proposed right of way lines.

Distance and direction to the nearest town.

Location of all roads, streets, and detours.

Geotechnical investigations for the foundation design including thelocation of soundings, and test holes with logs showing the elevations atwhich the various types of materials are encountered and the watertable level.

Location of existing and proposed drainage.

A longitudinal section showing the existing ground levels on the roadwaycentre line, proposed grade line, and high, normal and low waterelevations where applicable, to natural scale.

Horizontal and vertical curve data.

River flow direction (for a river bridge).

Direction of True North.

7.3.2 Additional Data for Grade Separations (Highway/Rail)

A plan of all rail tracks located within 150 meters of the centreline of theproposed highway should be compiled and should include the following data:

Destinations of the railway lines.

Radius of curvature, if any

The position of the beginnings and ends of transition and circular curves.

Distance from centre to centre of tracks and distance from trackcentreline to right of way line.

Angle between centreline of highway and centreline of each track.

Rail distance of the established railway centreline and the crossing angleat the point of intersection.

Distance from the crossing point to the nearest rail kilometre post.

Position of switch points, frogs and other track appurtenances.

Position of future tracks, if known.

Cross sections accurate to 3.0 mm taken along railway for 150 meters oneach side of the intersection (take elevations on top of each rail).





The difference in level between the railroad datum and the highwaydatum, if any.

Distance to the nearest station and signals.

7.3.3 Additional Data for Grade Separations (Highway/Highway)

Prepare a locality plan of the proposed structure and include the following dataregarding the existing highway:

Destinations of roads.

Alignment (horizontal and vertical).

Degree of radius of curvature.

The position of the beginnings and ends of transition and circular curves.

Width of travelled roadway and of the roadbed from shoulder to shoulder.

Kilometre distance of the point of intersection on both roads and theangle of intersection.

Cross sections taken along roadway for a distance of 150 meters oneach side of the intersection.

7.3.4 Additional Data for Waterway Crossings

Where a proposed structure crosses a waterway, the following supplementarydata is required:

A contour plan, stream cross sections and aerial photographs.

Complete data on existing bridges upstream and downstream, includingdates of construction and performance during past floods.

Available high water marks with dates of occurrence.

Information on debris and channel stability.

Factors affecting water stages such as high water from other streams,reservoirs, flood control projects and tides.

The existence of any dams upstream or downstream.





7.4 ANNEX: CHECKLISTS FOR ROAD SAFETY AUDITS

These checklists are obtained from the Road Traffic Management Corporation of South Africa, but similar checklists can be obtained form the Department of Transport in theUnited Kingdom, USA or other countries.

7.4.1 Preliminary Design Checklist





7.4.2 Detail Design Checklist

Code of Procedure v1.0 DraftFinal

Documents

Transcript of Code of Procedure v1.0 DraftFinal