INDUCTION TRAINING REPORT – PLANNING DIVISION

ACKNOWLEDGEMENT
I thank the almighty God for making my training period successful. I wish to acknowledge the
following people who delved much into my training and made it successful; Mr. Atsu Amedzake
(The Director of Planning), Mr. Annan, Mr. Archibald Dery, Mr. John Acquah, Rev. Amoako
and the entire Staff and Management of Ghana Highway Authority

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TABLE OF CONTENTS

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CHAPTER ONE

INTRODUCTION TO PLANNING

1.1 Background

The Ghana Highway Authority is one of the road agencies under the Ministry of Roads and
Highways. Their mission is to provide a safe and reliable trunk road network at optimum cost by
taking advantage of modern technology in road building and new income generating methods to
facilitate socio-economic development in the country.

The Ghana Highway Authority has eight divisions within which trainees go through each
division within a specified period to understudy the various Engineers and learn all the
engineering processes in that Division. My training program had me scheduled to start with the
Planning Division. The Planning Division of the Ghana Highway Authority is under the
Development Department.

The division is responsible for the collection, analysis and evaluation of traffic, transportation,
land use and developmental data. It also recommends desirable modifications of the planned
highway system and long term capital development projects.

The Planning Division also makes analysis of the economic benefits expected and actually
derived from planned and constructed trunk roads; compiles reports on vehicle importation and
registration, fuel consumption, vehicle operating cost, road user taxes, freights and passenger
rates.

The Division maintains the up-to-date inventory of all existing roads and bridges to determine
their condition and geometric features. It also develops comprehensive maps of the entire
highway system of the Authority detailing the rights-of-way clearly.

I was attached to the division for two months induction training, from June to August, 2013.The
objective of the two months induction training in the planning division is for trainees to under
study the Engineers in their various duties in the division.

The Planning Division is divided into five main units namely; Network Planning, Traffic
Engineering, Project Monitoring & Evaluation, Regional Corridor Project & Private Road
Finance and Transport Economics units.

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The Planning Division performs the following main functions:

 Traffic studies
 Axle load studies
 Procurement of consultants

1.1.1 Traffic Studies

Traffic studies are carried out on the trunk road network and reports compiled periodically. The
information obtained is invaluable for the planning process. Forecasts of future traffic can be
made, improvements can be made where needed etc. Some common traffic studies undertaken
include traffic volume counts, spot speed studies, origin- destination studies and junction delay
studies among others.

1.1.2 Axle load studies

Axle Load Studies are done to enable the nature of loadings on the trunk road network to be
determined. This is important for the design of highway pavements. It is not sufficient to base
designs on legal axle load limits because of the widespread problem of overloading.

1.1.3 Procurement of consultants

Most of the consultancy services needed by the Ghana Highway Authority are outsourced to
private consultants whilst a small proportion is done in-house. Consultants are procured under
terms of reference to undertake one or more of the following:

 Feasibility studies
 Detailed design studies
 Supervision of construction works

Majority of development projects undertaken are funded by development partners. Contract

documents are prepared for consultancy services depending on the donor agency sponsoring the
project. Thus, the activities for procuring a consultancy firm for services related to a project
being financed by the World Bank will have the Procurement of consultants and contract
documents being prepared according to World Bank guidelines.

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1.2 Organizational Structure of Planning Division

The division is under the Development Department of the Authority. It is headed by a director. In
the division are five major units headed by their respective mangers. These are; the Traffic
Engineering Unit, Transport Economics Unit, Network Planning Unit, Project Monitoring and
Evaluation Unit and the Regional Corridor Project & Private Road Finance Unit.

Director of
planning

Secretary/
Administrative
Workers

Traffic Network Regional Project

Transport
Engineering Planning Corridor Monitoring &
Economist
Manager Manager Projects Evaluation

Network Planning Planning Planning

Traffic Engineer
Engineer Economist Engineer Engineer

Traffic Operations Technician Technician

supervisor Engineer Engineer

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1.2.1 Traffic Engineering Unit

The Traffic Engineering Unit is responsible for:

 Traffic Data Collection

 Traffic Data Analysis and Forecasting

 Traffic Signal Installation

 Axle Load Survey & Analysis

 Traffic Management

1.2.2 Transport Economics Unit

The Transport Economics Unit is responsible for:

 Analysis of economic benefits expected or actually derived from planned and constructed
highways

 Compilation of reports on vehicle importation and registration

 Collection of data on fuel consumption, vehicle operating costs, road users taxes, freight
and passengers rates

 Preparation of Annual Budget

1.2.3 Network Planning Unit

The Network Planning Unit is responsible for:

 Development of comprehensive maps of the entire highway of the Authority in detail; 

 Classification of the trunk road network;

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 Orderly planning of heavy vehicle and dangerous goods routes;

 Planning and provision of public transport routes;

 Planning and provision of pedestrian and bicycle routes;

 Identifying the effects of development decisions in and on surrounding areas and

roadways;

 Development design that facilitates urban design principles such as accessibility,

connectivity, efficiency, amenity and safety;

1.2.4 Project Monitoring & Evaluation Unit

The Project Monitoring & Evaluation Unit is responsible for:

 Ensuring that all proposed projects are delivered within the set time frame

 Provision of measures to speed up projects which are behind schedule

 Ensures that the objectives of a project are met

 Collection of data on completed projects to ensure that lessons learnt can be applied in
similar projects in the future

1.2.5 Regional Corridor Project & Private Road Finance Unit

Regional Corridor Project & Private Road Finance Unit is responsible for:

 The effective planning and implementation of the Regional Corridor Project

 Participation of the Private Sector in the finance of road projects

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1.3 Road Classification

The trunk roads network is classified into three main categories namely:

 National Roads

 Inter Regional Roads

 Regional Roads

1.3.1 National Roads:

These are roads that link the national capital to other regional capitals and neighboring countries.
They have the prefix “N” and up to two digits such as N1, N11. On the highway road map, all
the national roads lying horizontally have odd numbers such as N1, N3 etc whiles those lying
vertical have even numbers. These types of roads normally have a carriageway width of 7.3m
and shoulder width of 2.5m.

1.3.2 Inter Regional Roads:

These are roads linking one region to another. They have a numbering system preceded with the
prefix “IR” and up to two digits e.g. IR8, IR11. The dimensional specifications for Inter
Regional roads are 7.3m for the carriageway width and 2.5m for the Shoulder.

1.3.3 Regional Roads:

These roads link district capitals to their respective regional capital in addition to other nearest
district capital and major industrial centers. They have a numbering system preceded with the
prefix

“R” followed up to 3 digits e.g. R124. These types of roads normally have a carriageway width
of 7.3m and shoulder width of 1.5m.

This system is very easy to use due to its grid system of numbering. It is observed that from
south to north, odd numbers progress higher in magnitude, whilst even numbers progress from
east to west. An example is the National Road from Kumasi (N10) northwards, through Tamale

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(N10) to Bolgatanga (N10). Another is the road westward from Accra (N1) through Cape Coast
(N1) to Sekondi (N1).

1.4 Transportation Problems

Despite the obvious benefits, transportation also comes along with numerous problems which
can negate its positives left unchecked. The challenge therefore is for transportation engineers
and planners to balance society’s need for fast and efficient transportation with the costs
involved. Common problems associated with the transportation system include using up
enormous resources of energy and land; fatalities from accidents; congestion and time wasting;
environmental pollution; and global warming among others.

1.4.1 Land Consumption

The territorial imprint of transportation is significant, particularly for the automobile. Between
30 and 60% of a metropolitan area may be devoted to transportation, an outcome of the over-
reliance on some forms of urban transportation.

1.4.2 Fatalities from accidents

Growing traffic in urban areas is linked with a growing number of accidents and fatalities,
especially in developing countries. Accidents account for a significant share delays. As traffic
increases, people feel less safe to use the streets.

1.4.3 Congestion

Congestion is one of the most prevalent transport problems in large urban agglomerations. It is
particularly linked with motorization and the diffusion of the automobile, which has increased
the demand for transport infrastructures. However, the supply of infrastructures has often not
been able to keep up with the growth of mobility.

Factors leading to congestion include;

 Poor roads
 Poor design
 Driver attitude

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 Traffic signal (timing, power outage and coordination)

 Construction works
 Too many accesses

1.4.4 Environmental impacts and energy consumption

Pollution, including noise, generated by circulation has become a serious impediment to the
quality of life and even the health of urban populations. Further, energy consumption by urban
transportation has dramatically increased and so the dependency on petroleum.

1.5 Solutions to transportation problems

Solutions when carefully thought of and planned lead to huge economic benefits for society.
Decreased travel time and reduction in fuel consumption are some benefits of solving
transportation problems. Other forms of benefits are:

 Promotes non-motorized traffic.

 Reduces traffic delays.
 Shifts peak-hour travel.
 Promotes public transport.
 Reduces the length of a trip.
 Promotes car pooling.
 Reduces the need to make a trip.
 Shifts travel from congested locations

1.5.1 Land Use Approach:

The land use planning approach seeks to influence settlement patterns so as to increase the
accessibility of jobs, shops, educational institutions etc. without the need to travel by car; or
when travel by car is essential, by minimising its usage and shortening the distance travelled.
The land use approach is normally accompanied by other measures that make urban centres more
attractive than peripheral settlements and promote choice by increasing the relative advantage of
travel other than by car.

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1.5.2 Car Park Control:

This concept seeks to promote public transport usage and reduce congestion especially for the
journey to work trip by car parking control. Control measures used include:

 Imposing cordon charges in controlled areas and parking spaces within the cordon.

 Limiting the continuous length of time during which a car may stay in a controlled
parking space so that commuters are discouraged from riding in their cars to the city
centre.

 Minimising the number of available parking spaces to commuters.

A high level of enforcement of parking regulations, including the prohibition of illegal parking
on roads in the city is essential if maximum benefits to public transport are to be achieved from
parking control.

1.5.3 Park and Ride:

In this model, vehicle owners park their cars at the periphery of central business districts. They
are then connected to the busy centers by public transport such as bus or train. This goes a long
way in ensuring that congestion due to private vehicles is reduced. Used in conjunction with
parking control, park and ride achieves good results.

Staggering of Working Hours:

This is a flexible approach in which a large number of employees agree to stagger their start and
finish times with no change to the number of hours worked each day. The workers start and
finish work each day at time of their own choice as long as a core period is worked out for each
day. With a compressed form of this approach, workers may work many hours per day for fewer
days per week or per fortnight. Staggered working hours has the effect of decreasing congestion

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during the peak hours by reducing the demand for public and private transport during the most
heavily loaded peak hours.

1.5.4 Car Pooling:

Car pooling puts drivers of single-occupancy vehicles into fewer vehicles thereby reducing the
number of vehicles on the road leading to a decrease in traffic congestion. Car pooling can be
formal or informal. That is it can be done by a group of individuals who share the driving and
thereby reduce the cost of driving alone, or organized by an employer or a governmental agency.
Car pooling is most appropriate when the participants have the same travel schedule each day or
work in the employment and when trips to work are long so that time spent gathering the
occupants is relatively small. Coordinated and executed successfully, car pooling can be
magnified to van pooling. However van pooling is not as popular as car pooling due to the larger
number of people involved. The downside of car pooling is that it may not be advantageous to
staff who don’t start work and close at the same time.

1.5.5 Public Transport:

The use of public transport is a major scheme which reduces congestion to a large extent in
cities. However the key to encouraging people to patronizing public transport is to provide clean,
comfortable and respectable vehicles with services regular and predictable. For bus public
transport, public patronage will improve if limited stop service systems are used with bus control
systems which give priority to buses over cars on congested roads. The proposed Bus Rapid
Transit System is an example of bus transport used in other countries. Bus priority measures in
widespread usage include:

 Priority lanes that allow buses to travel the wrong way on one way streets to avoid a
detour.

 Reserved bus lanes on, or that provide access to, urban motorways.

 Reserving some streets for only buses. Such streets are known as “bus only” streets.

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 Using traffic regulations to give priority to buses when using congested roads.

 Providing exemptions to buses from prohibitions at intersections which enable them to

bypass queues of vehicles at intersections and approaches to signal controlled
intersections.

Dedicated bus lanes require constant policing to ensure that they are allowed to operate
efficiently without being interfered with by private cars. An alternative is to operate these bus
lanes in the mornings and evenings during peak periods when traffic congestion is at its height.

1.5.6 Use of Technology:

Advances in technology provide a means to solve transportation problems. A coordinated system

exists where control of traffic lights and other traffic devices is done from a central point. This is
known as the Urban Transport Control (UTC) and is used efficiently to control the traffic
resulting from vehicles crowding on sections of the road. Traffic lights can be controlled in an
unconventional way by providing access to lanes where traffic has built up to a very high level.
The use of cameras at intersections also serves to control the behavior of drivers. Recalcitrant
road users caught on cameras committing traffic offences can be apprehended and sanctioned.
Under the guise of being functional, inoperative cameras can also be installed at intersections;
this keeps drivers in check.

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CHAPTER TWO

PROJECT FINANCING, PREPARATION, APPRAISAL AND

EVALUATION

2.1 Sources of Funding

Road construction projects are capital intensive and have traditionally been a big challenge for
governments especially of developing countries. Assistance is therefore sought from
development partners to help meet objectives in this regard. In Ghana, road and transportation
sector investment is supported by the following sources of funding:

 Road Fund
 Consolidated Fund
 Loans, credits and grants from bilateral and multilateral donors

2.1.1 Road Fund

As part of the structural adjustment programme adopted in 1983, the Government of Ghana was
required to establish a source of funding for road maintenance before any loans could be granted
for the construction of new roads. This led to the establishment of the Road Fund in 1985 under a
legislative instrument with the aim of having a source of funding for road maintenance.

During the early days of the fund, it was confronted with challenges among which included the
following:

 Revenue from the fund covered less than 35% of required funding
 Lack of any financial management system and effective oversight
 Releases to the road agencies were erratic and cumbersome
 No feedback from agencies on use of funds, no monitoring.
 No control over projects financed – possibility of diversion of funds

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Due to the above mentioned difficulties, the Road Fund was restructured in 1997. It was
enacted into law by the Road Fund Act(Act 536) which provided for the establishment of the
fund, oversight board, and a management and financial framework.

Revenue Generation

Sources of Revenue into the Road Fund include the following:

 Fuel Levy -collected by Customs Excise and Preventive Service (CEPS) - constitutes
90% of revenues (95% in 1997)

 Vehicle registration Fees - Collected by DVLA

 Road User fees -Collected by DVLA

 Road and Bridge Tolls –Collected by Private Contractors

 International Transit Fees -Collected by Customs Excise and Preventive Service (CEPS)

The Fund is basically utilized for the following Activities:

 Routine and Periodic Maintenance of roads

 Upgrading and rehabilitation of Roads

 Road safety activities

Funds are Disbursed Through:-

 Ghana Highway Authority (GHA)

 Department of feeder Roads (DFR)

 Department of Urban Roads (DUR)

 National Road safety Commission (NRSC)

Management of the Fund

 Secretariat responsible for revenue collection and disbursements

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 Monthly financial Statements and Reports -goes to Board Members, Agencies,

Ministries, Donors

 Board meets regularly -for policy and direction

 Annual Report sent to Parliament through Minister

 Extract of Annual Report published in local papers

 Outreach programmes to educate the Public: –Public Fora, Press Publications, Radio &
T.V. discussions etc.

Monitoring

 Monthly Accounting and Reporting

 Field Inspection visits -By Road Fund Board, Secretariat Staff, Ministry of Roads and
Highways staff

 Payment Approval Procedure

 Payment and Performance Reports from Agencies

 Year End External Financial and Technical Audits

2.1.2 Consolidated Fund

The Consolidated Fund is a Public Fund enshrined in the Constitution of Ghana. This provides
the financial support for government transactions (i.e. source by which administrative expenses,
salaries, allowances and the benefits of staffs of government institutions are paid). Its sources of
replenishment are the taxes and other revenues collected by the Government.

The main focus of this fund in the road sector is the provision of counterpart funding for donor
supported reconstruction works and GOG’s development works. The Government uses the
consolidated fund to supplement the Road Fund to support development like rehabilitation,
reconstruction and new construction.

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2.1.3 Development partners

The Government of Ghana (GOG) receives funding from its development partners in the form of
grants, loans and credits.

The various development partners of the GOG have various criteria by which a particular road
project can be selected for funding. They all have a particular cycle through which any project is
taken. This cycle is called the Project Cycle and it varies from one development partner to the
other, but they all have some common features. The Project Cycle consists basically of Project
Identification, Preparation, Appraisal, Negotiation, Implementation and Evaluation.

The Project Cycle is the means by which the development partners ensure that the most
economically and socially viable projects are selected for funding. The Cycle also helps the
development partners to ensure that monies allocated for particular road projects are judiciously
used and are not diverted for other projects by the GOG. The development partners are also able
to make sure that the quality of the construction works are not compromised in anyway.

One of the Development partners of the GOG is the World Bank and the Project Cycle of the
World Bank is taken as an example and discussed into details below.

2.2 The World Bank project cycle

There are six phases involved in a typical World Bank project cycle:

 Identification
 Preparation
 Appraisal
 Negotiation and Board presentation
 Implementation and Supervision
 Evaluation

The recipient country has full responsibility for the design, preparation and implementation of
individual projects. The donor is deeply involved in each of these stages. The Bank however is
solely responsible for the Appraisal and evaluation stages.

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2.2.1 Project Identification:

The World Bank lends money to low and middle-income countries to support development and
change. Borrowing countries have the responsibility for the design, preparation and
implementation of individual projects with the Bank deeply involved in all of these stages. The
World Bank works with a borrowing country’s government to determine how financial and other
assistance can be designed to have the largest impact.

The Bank begins by studying the economy of the country and the needs and priorities of the
sector in which the lending is being contemplated. The identified sectors may range across the
economic and social spectrum from infrastructure, to education, health or government financial
management. Studies and investigations are carried out with the government to agree on an
initial project concept and its beneficiaries, and the World Bank project team outlines the basic
elements in a Project Concept Note. This is a document which identifies proposed objectives,
imminent risks, alternative scenarios and a likely timetable for the project approval process. .
Two other Bank documents are generated during this phase. The Project Information Document
contains useful public resources for tailoring bidding documents to the proposed project, and the
publicly available Integrated Safeguards Data Sheet identifies key issues related to the Bank's
safeguard policies for environmental and social issues.

2.2.2 Project Preparation:

The World Bank incorporates projects into a lending program after which negotiations between
the Bank and the borrower begins. This is after there has been a mutual agreement on project
objectives. The project preparation can take several years because it entails developing an idea
into a detailed proposal that considers all aspects of the project: technical, economic, financial
and institutional. It takes several years to conduct feasibility studies and prepare engineering and
technical designs. The government may be required to employ consultants and other public
sector companies for goods, works and services.

The Word Bank generally takes an advisory role and offers analysis and advice when requested
during this phase. For instance, the Bank may help arrange financing for consulting services
during this stage. It may also provide special technical assistance and engineering loans,

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reimburse the borrower for preparatory work with proceeds of the proposed loan, include funds
for preparatory works for a subsequent project of the same sector among others.

The Bank again assesses the relevant capacity of the implementing agencies at this point in order
to reach an agreement with the borrower about arrangements for overall project management,
such as the systems required for financial management, procurement, reporting, and monitoring
and evaluation.

It is also important for borrower to prepare an environmental impact and social assessments
reports as prerequisites for funding. The reports analyze the planned project’s likely
environmental impact and describe steps to mitigate any possible harm. From a social point of
view, various studies aimed at analyzing a project's potentially adverse effects on the health,
productive resources, economies, and cultures of indigenous peoples may be undertaken. At this
stage, it is important to note that the borrower’s commitment of the project is essential not only
for preparation, but the overall successful implementation.

2.2.3 Appraisal:

Appraisal provides a comprehensive review of all aspects of the project and lays the foundation
for implementing the project and evaluating it when completed. Appraisal is solely the Bank’s
responsibility. It is conducted by Bank staff, sometimes supplemented with individual
consultants. The consulting team usually comprises a multi-disciplinary mission that spends
three to four weeks in the country. Appraisal covers four main aspects of the project: technical,
institutional, financial and environmental.

Technical Appraisal:

The technical appraisal ensures that the project is soundly designed, appropriately engineered
and follows accepted standards for development. Technical appraisal is concerned with questions
of physical scale, layout, and location of facilities; what technology is to be used, including types
of equipment or processes and their appropriateness to local conditions, what approach will be
followed for the provision of services among others. An essential part of this kind of appraisal is
a review of the cost estimates and the engineering or other data on which they are based to
determine whether they are accurate within acceptable margins and whether allowances for

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physical contingencies and projected price increases during implementation are adequate.
Procurement arrangements are reviewed to make sure that they conform to the requirements of
the Bank.

Institutional Appraisal:

The institutional capacity of a country in a large extent determines the ability of a country to
implement and manage projects. It is essential for the country to develop a viable institution to
cover not only the borrowing entity itself, its organization, management, staffing, policies and
procedures which enable institutions to operate efficiently. A great deal of attention is therefore
given to identifying the personnel and the institutional relationships necessary to implement the
project.

Financial Appraisal:

Financial appraisal ensures that there are sufficient funds to successfully finance the costs of
implementing the project. The bank does not normally finance the total cost of a project;
typically, it finances foreign exchange costs and expects the borrower or the government to meet
the local costs. Financial appraisal is also concerned with financial viability especially if the
project design includes revenue generating output. Financial appraisal is also concerned with
recovering investment and operating costs from project beneficiaries. The Bank’s policy is to
strike a balance between considerations of equity, the need to use scarce resources efficiently,
and the need to generate additional funds to replicate the project to reach larger members of
potential beneficiaries.

Environmental Appraisal:

Environmental Assessment is the responsibility of the recipient government. Environmental

Assessment ensures that environmental considerations are given adequate weight in project
selection; siting and designing decisions and that Environmental Assessments do not delay
project processing. Environmental Assessment examines and reduces the likely environmental
impacts of a project prior to its implementation. Environmental Assessment is a legal
requirement in a lot of countries for certain types of development projects. Project Specific EAs
are used to examine specific investment projects and should normally cover:

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 Existing environmental baseline conditions;

 Potential environmental impacts, direct and indirect, including opportunities for
environmental enhancement;
 Systematic environmental comparison of alternative investments, sites and design;
 Preventive, migratory and compensatory measures;
 Environmental management training;
 Environmental monitoring.

Project Appraisal Document:

Once all project details are negotiated and accepted by the government and the World Bank, the
project team prepares the Project Appraisal Document (PAD) in which its findings and
recommendations for the proposed project are made to the Bank’s management. The cost
estimates, financing plan, an implementation schedule and recommendations reached between
the Bank during negotiations to ensure that the project will be carried out in an economic and
efficient manner are included in the PAD.

2.2.4 Negotiations, Board Presentation:

Negotiation is the stage at which the Bank and the borrowing government endeavor to agree on
the measures necessary to assure the success of the project. These agreements are then converted
into legal obligations, set out in the loan documents. All of the principal issues that have been
raised prior to and during appraisal are dealt with in the loan documents. Drafting and
negotiations of the legal documents go to show that the Bank and borrower are in agreement on
specific actions necessary to achieve success in the project implementation. After negotiations,
the appraisal report is amended to reflect the agreements reached together with the President’s
report and the loan documents is presented to the Bank’s Executive Directors.

2.2.5 Implementation and Supervision:

The next stage in the life of the project is its actual implementation over the period of
construction and subsequent operation. Implementation is the responsibility of the borrower.
Supervision is the least glamorous but most important part of the project work. This is because

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no matter how well a project is prepared and appraised, its development benefits can only be
realized when it is properly executed. Problems in implementation arise when there are changes
in economic, political and other circumstances. In such a situation, it may be necessary to modify
the operational plan in order to meet the original project objectives. A very important element in
project implementation is the procurement of goods, works and services. This is critical in the
timely implementation of the project. Delay in procurement leads to delay of project completion
and an increase in investment costs. The Bank therefore makes provisions for procurement to be
carried out by specific methods in accordance to its guidelines.

2.2.6 Evaluation:

The Bank’s independent Operation Evaluation Department (OED) assesses the performance once
the project is completed and the loan fully disbursed. This group is entirely separate from the
operating staff of the Bank and reports directly to the Board of Directors. The Evaluation
measures outcomes against the original objectives, sustainability of results and institutional
development impact. These results are taken into consideration in the design of future projects.
The Evaluation completes the steps of the project cycle.

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CHAPTER THREE

VALUATION IN PLANNING AND HDM – IV

3.1 The Valuation Process

Construction of a road affects the lives of people along the project corridor. The evaluation of the
value of property and other aspects of the lives of project affected persons due to the road project
is known as valuation. Things affected may include immovable property such as houses which
may be demolished, crops destroyed in the road corridor due to winning of materials and
construction of the road, livelihood of people selling along the road, squatters among others.

The valuation office at Ghana Highway Authority is under the Contracts Division. Valuers go
out on the field to take data on the project affected people. Interviews are conducted with people,
photographs are taken and values of structures are taken.

The principle of the valuation is that compensation paid out to the project affected persons
should enable them to acquire property higher in value compared to what they lost. The
determinant of the compensation paid is known as the disturbance. Disturbance is worked out by
using a formula which considers many factors such as the location and value of the property. For
instance, a house close to the road has a higher value than one located in the hinterland.
Similarly, a higher compensation is paid on a property which has got history and heritage or
religious value than one which does not.

It is within the right of a project affected person to accept or reject compensation offered him.
The value of the property being compensated is first verified by valuers at the Lands
Commission. Compensation will only be paid out if this verification is done. Fifty percent of the
compensation validated is paid to affected persons. Dissatisfied project affected persons can go
to court to demand for better compensation. The value decided by the court is binding on both
parties. The downside of court action is that the project may be delayed for a long time pending
the decision of the court.

Compensation is not paid directly by donors but by the Government and neither is the relocation
of utilities. One of the requirements of a donor funded project is for a Socio-Economic Impact

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Assessment of the project to be carried out. This also forms a basis for the value of compensation
to be paid due to the social impacts of the project. A Government of Ghana counterpart fund
(matching fund) is allocated for compensation and relocation purposes. Contingent upon this,
loans from the donor will then become effective. It is possible for the recipient of the loan to
negotiate for the matching fund to be spread out through a period.

3.2. Introduction to HDM-IV

The Highway Development and Management Tool (HDM –4) was developed to replace the
other highway management software which was called Highway Design and Maintenance
Standards Model (HDM-III). The HDM-4 tool provides a powerful system for the analysis of
road management and investment alternatives. The uses of HDM – 4 are varied and many and
some of them are:

3.2.1 HDM-4 Analytical Framework

The HDM-4 is an important tool in the prediction of certain key parameters over the life cycle of
a road pavement which is typically 15 to 40 years. These are:

 Road deterioration.

 Road work effects.

 Road user effects.

 Socio-Economic and Environmental effects.

HDM-4 allows a maintenance standard to be defined which measures factors affecting the rate of
pavement deterioration and riding quality of a road measured in terms of the International
Roughness Index (IRI). Factors of pavement deterioration include:

 Traffic loading.

 Environmental weathering.

 Effects of inadequate drainage systems.

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Furthermore, these factors of road deterioration, the impact of road condition, design standards,
vehicle operating costs, climate and their impacts on road users in the form of road user costs can
be computed by HDM-4.

3.2.2 HDM-4 in Strategy Analysis:

Strategic planning of medium to long-term road network expenditures requires that a road
organization should consider the requirements of its entire road network asset. HDM-4 helps to
analyze and choose the most appropriate budget within constrained or unconstrained economic
conditions. Strategy analysis can be used to analyse a chosen network as a whole to prepare
medium to long range planning estimates of expenditure requirements for road maintenance or
development under different budget scenarios. Use of HDM-4 in this regard includes:

 Medium to long term road network performance under varying levels of funding.

 Forecasts of long term road network performance under varying levels of funding.

 Optimal allocation of funds to sub-networks.

 Optical allocation of funds to according to defined budget definitions.

 Analysis of policy changes.

3.2.3 Project Analysis:

Project analysis involves the evaluation of one or more road projects or investment options.
HDM-4 analyses the economic or engineering viability of road investment projects by
considering the following issues:

 The structural performance of road pavements.

 Life-cycle predictions of road deterioration, road work effects and costs.

 Road user costs and benefits.

 Economic comparisons of project alternatives.

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3.2.4 Implementing HDM -4 within a Road Management System:

The HDM -4 is used efficiently as a decision support component within a complete road
management system. In Ghana Highway Authority, for maintenance activities, HDM -4 is used
as a decision support for the Pavement Maintenance and Management Programme (PMMP). The
two programme work together in an integrated manner for:

 Data collection.

 Database management.

 Decision support.

 Management information.

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CHAPTER FOUR

ROUGHNESS AND VOC STUDIES

4.1 Pavement Evaluation

It is the planning division’s duty to ensure the efficient management of the road network system
under GHA. One method is to periodically assess the road pavement.

Pavement evaluation is a process by which the state and conditions of existing pavements are
assessed in relation to its performance.

The road pavement is designed to provide users with comfortable safe and efficient service. In
view of these functions, the pavement must possess sufficient structural capacity to support the
combined effect of traffic loads and environmental conditions.

To determine how a pavement is performing at a particular point in time and to predict how it
will perform in the future, regular monitoring should be done to establish whether its three basic
functions are being fulfilled.

The scope of a pavement evaluation is to record pavement characteristics. A pavement

evaluation can be classified as functional or structural depending on which characteristic is being
surveyed.

4.1.1 Functional Evaluation: a functional evaluation provides information about surface

characteristics that directly affect users’ safety and comfort or serviceability. The main
characteristics surveyed are skid resistance and surface texture in terms of safety as well as
roughness in terms of serviceability.

4.1.2 Structural Evaluation: this provides information on whether the pavement structure is
performing satisfactorily under traffic loading and environmental conditions. Surveyed
characteristics include pavement distresses and structural properties. Note that, some pavement

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distresses indirectly lead to functional problems such as asphalt pavement bleeding, which
effects skid resistance or faulting in jointed concrete pavement which affect roughness.

Pavement Characteristics and Indicators Considered in a Condition Evaluation:

 Roughness
 Texture
 Skid Resistance
 Structural Properties
 Surface Distress.

4.2 Roughness:

Pavement Roughness is defined as the ratio of the sum of the vertical elevation to horizontal
length. It is an indication of the riding quality of a road. It is the deviations of a pavement surface
from a true planar. Roughness is thus associated primarily with serviceability. However,
roughness is also related to structural deficiencies and accelerated pavement deterioration.

Roughness affects vehicle operating costs, safety, comfort and speed travel. Roughness is the
primary criteria by which road users judge pavement performance, and therefore, the condition
of a highway system. Riding quality is without doubt a very important factor for the road user. It
influences the type and magnitude of maintenance activities required as well as the maintenance
costs.

4.3 Causes of Roughness:

Roughness is caused by a combination of factors acting singularly or in concert. Some are:

 Improper design of the pavement structure. Designs which fail to account adequately for
traffic expected to use the pavement may lead to failure. The failure results when the
structural capacity of the pavement has been exceeded by the traffic using the road.

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 Overloading of the pavement leads to structural failure and hence a rough characteristic
of the road being noticed.

 Improper design and construction of hydraulic aspects of the road leads to an early
deterioration of the pavement and in time the road becomes rough.

 Bad construction practices and lack of supervision also results in the road failing. This
leads to the road becoming rough.

4.4 Evaluation of Roughness:

Approaches used to evaluate the roughness of a pavement are the Present Serviceability Rating
(PSR) which has led to an objective quantitative index, the Present Serviceability Index (PSI)
and the International Roughness Index (IRI).

4.4.1 Present Serviceability Rating (PSR):

This system of rating is based on individual observation. Present Serviceability Rating is defined
as the judgment of an observer to the current ability of a pavement to serve the traffic it is meant
to serve. A scale which has been developed ranges from 5 (excellent) to 0 (essentially
impassable). Since PSR is based on passenger interpretations of ride quality, it generally reflects
road roughness because roughness largely determines ride quality.

Figre 9.1: Individual Present Serviceability Rating Form.

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4.4.2 International Roughness Index (IRI):

The IRI was developed by the World Band in the 1980’s. IRI is used to define the characteristic
of the longitudinal distance along a travelled track on a road. It is defined as a mathematical
property of a two-dimensional road profile. This shows the elevation of the road as it varies with
longitudinal distance along a travelled track. A quarter-car math model is used to replicate
roughness measurements that were done decades before using other methods.

IRI Roughness Scale

4.4.2.1 Significance of the IRI:

The determination of the roughness index is important due to the following reasons:

 The IRI helps to determine the extent of damage of the road surface at a given section
thus giving an indication of the extent to which the current condition of a road departs
from the acceptable standard.

 The greater the IRI, the higher the extent of damage. Hence it gives an indication of the
kind and magnitude of maintenance activities that may be needed for a given section of
the road.

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 This also implies that the cost of maintenance for road sections with higher IRI will be
more than sections with lower IRI. (i.e. more money is needed to bring roads with higher
IRI to an acceptable level than roads with lower IRI)

 The greater the IRI, the higher the vehicle operating costs and the lower the comfort
experienced by the rider.

4.5 Roughness Measurement:

Roughness measuring devices are classified by the ASTM E 950-94 standard into four groups
according to their accuracy and methodology used to determine IRI. Class I devices incorporate
precision profiles, Class II devices use IRI estimates from correlation equations and Class IV
considers subjective ratings and uncalibrated measures.

Examples of Precision profiles are portable laser profilers and non-contact lightweight profiling
devices. Class II profilometer methods include APL profilometer, profilographs (eg. California,
Rainhart), optical profilers and inertial profilers. IRI estimates from correlation equations are
done by Roadmaster, Roughometer, TRL Bump Integrator. Class IV which is subject ratings and
uncalibrated measures can be done by Key code rating systems, visual inspection and ride over
section.

4.5.1 Response Type Road Roughness Meters (RTRRMs):

Class III category of roughness data collection equipment is the response type road roughness
meters (RTRRMs), often called "road meters".  RTRRM systems are adequate for routine
monitoring of a pavement network and providing an overall picture of the condition of the
network.  The output can provide engineers with a general indication of the overall network
condition and maintenance needs

RTRRMs measure the vertical movements of the rear axle of an automobile or the axle of a
trailer relative to the vehicle frame.  The meters are installed in vehicles with a displacement
transducer on the body located between the middle of the axle and the body of a passenger car or
trailer.  The transducer detects small increments of axle movement relative to the vehicle body. 
The output data consists of a strip chart plot of the actual axle body movement versus the time of

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travel. The equipment in use to measure roughness at Ghana Highway Authority is the
Roughometer which is a type of RTRRM.

4.6 Vehicle Operating Costs

Vehicle Operating Costs are the costs incurred by road users when they travel over a portion of
the road. Vehicle Operating Cost (VOC) is measured as Vehicle Operating Cost per vehicle.
VOC is used to measure the effect an intervention has on a road scheme. Owners and users of
vehicles profit when a road improvement is undertaken. Higher average speeds can be
maintained and this leads to more even running and subsequently, savings in fuel consumption.

VOC depend on the number and types of vehicles using the road, the geometric design standards
of the road, particularly the curvature, gradient and road width, the condition of the road
primarily its roughness and driver behavior.

4.6.1 Computation of Vehicle Operating Costs:

Computer models are available for assisting in the calculation of vehicle operating costs under a
range of conditions and estimating vehicle operating cost savings as a result of road projects.
Examples are micro-RTIM2 and HDM-III. Both of these models run on microcomputers and
simulate the performance of a road over time and under traffic. Costs and benefits are determined
by applying unit rates to quantities that are calculated. The units are supplied by the user by
using the current market rates which makes the models applicable of a wide range of economic
and financial environments. The effect on VOC is of the changing condition of the road surface
is taken into account in the determination of costs and benefits.

4.6.2 Data Requirements for VOC:

The Data input for VOC are divided into three different categories:

 Road Characteristics.

 Vehicle Characteristics.

 Climate.

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 Road Characteristics:

 Rise (m/km)
 Fall (m/km)
 Curvature (degrees/km)
 Roughness (m/km)
 Road Width (m)
 Surface Moisture Content for Gravel and Earth Roads (percent)
 Rut depth (mm)

Vehicle Characteristics:

 Free Speed in the Environment under Consideration(km/hr)

 Vehicle Weight (tonnes)
 Power to Weight Ratio (bhp/tonne)
 Vehicle age (km, year)
 Annual Utilization (km,hr)
 Vehicle Price
 Tyre Price
 Price of Fuel and Lubricants (per litre)
 Price of Maintenance labour (per hr)
 Vehicle Crew Cost (per hr)
 Overheads.

Climate:

 Rainfall (mm/yr)

The user has to apply the best available estimates of the relevant physical quantities and vehicle
descriptors in order to arrive at valid cost estimates whether using the tables or one of the
investment models.

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4.7 Importance of Data Items:

4.7.1 Physical Parameters of the Road:

Average rise and fall is important in that it relates directly to gear changes and hence fuel
consumption. The average rise and fall per kilometer must be measured separately. Its accuracy
depends on the amount of information available for the study.

Horizontal curvature is related to the gradient and sections of the road which are similar with
respect to rise and fall can be expected to have broadly similar horizontal curvature
characteristics.

Roughness which is related to the surface condition influences VOC directly. Roughness is
measured with a response type instrument such as TRRL Integrator Unit, NAASRA meter, Mays
Ride Meter.

On roads with greater width, running speeds of vehicles are high but on narrower roads, the
speeds are reduced. Therefore, an estimate of road width is required. On existing roads, a
reasonable estimate can be obtained by making a few sample measurements with a tape measure.

Surface moisture content on unpaved roads affects its slipperiness and hence the speeds of
vehicles. However, its effect on cost is small. Zero values are used for dry zones (annual rainfall
less than 750mm) and ranges up to six percent for very wet zones (annual rainfall greater than
1750mm).

The rut depth of unpaved road surfaces reduces the speeds of vehicles to a small extent. Rut
depth is measured under a two metre straight edge placed across the wheel track. Average values
varying from 10mm for unpaved roads in good condition to 50mm for roads in very poor
condition.

4.7.2 Vehicle Descriptions:

Free Speed of vehicles is defined as the average speeds at which different classes of vehicles will
travel on uncongested, flat, straight, smooth and wide sections of road in the particular
environment. These speeds are influenced by the general layout of the roads in the area due to

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the differences in driver behavior and vehicle performance. A vehicle speed survey is conducted
by the use of instruments such as a speed gun or any other empirical method. The speeds of the
various classes of vehicles are recorded on a flat, straight, smooth and wide section of the road.
The average speed for each class of vehicle will be the free speed for that class for the
environment under investigation.

Vehicle weight directly impacts negatively on fuel and tyre consumption. This is true for all
classes of vehicles; light vehicles, trucks and buses. The best estimates of vehicle weights are for
different classes of commercial vehicles can be found from axle-load surveys conducted on the
route under study.

Power to Weight Ratio is the net brake horse power per tonne of the gross vehicle weight. Axle
load surveys are an important way to provide information on the brake horse power of the
various classes of commercial vehicles using the route, and so enable the average brake horse
power per tonne of vehicle to be calculated.

In order to determine vehicle operating costs, vehicle age needs to be determined as the total
distance run since new as well as in years. The age in kilometers is a significant factor in
determining average vehicle repair costs and the age in years is used to determine depreciation.
Normally, average values for vehicle classes will be used in the calculation of the vehicle
operating cost components.

Annual Utilization in hours per year is used directly to determine annual crew costs and to
apportion annually accruing costs such as depreciation and overheads on to a kilometer basis so
that they can be related to usage on particular roads. Utilization in kilometers per year is
important because when multiplied by vehicle age, is used to determine spare parts costs.

Vehicle price aids in the computation of vehicle depreciation costs. In the operating costs tables,
the vehicle price is used to determine spare parts costs.

Both these costs are a significant proportion of the total cost and are highly sensitive to the initial
vehicle price. Good local data should be collected and this is normally easy to come by. Tyre,
fuel and lubricant prices information are easy to collect locally. Midyear values should be used.

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The price of labor maintenance is needed to determine the labor component of fitting spare parts
and repairing vehicles even though its contribution to vehicle operating cost is relatively small. It
is important that prices include all supervision and overhead costs otherwise underestimates will
be made. Prices will vary between countries and also within a country depending on the size and
type of workshop carrying out repairs.

Vehicle crew costs are determined by the by the number of crew that a vehicle carries, their
wages and the overheads of employing them. As in the case of maintenance labor prices, the
crew costs will depend on the size and type of organization operating the vehicle and unit values
should be based on weighted averages in a similar way.

Overheads are the components of vehicle costs which include such items as interest on capital
and garaging. Insurance costs may also be included as a surrogate for accident costs. The costs
vary from country to country and from company to company.

For road upgrading projects, vehicle operating costs should be estimated for the existing road
and the new developments.

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CHAPTER FIVE

TRAFFIC DATA COLLECTION AND ANALYSIS

5.1 Traffic Counts

Traffic counting and assessment helps to estimate future traffic loadings on the road or network
under review. In order to estimate the total traffic over the design life of the road, the first step is
to determine the current volume and type of traffic traveling on the road. Traffic counts are
conducted manually or automatically.

5.1.1 Manual Traffic Counts:

Manual Traffic Counts also called Classified Counts are carried out manually by teams of
observers recording vehicle numbers and other data types on sheets. Each vehicle is recorded on
a survey form according to the vehicle type. A survey period of one week is usually
recommended. Each direction is recorded separately and each hour is recorded on a separate
sheet.

5.1.2 Automatic Traffic Counts:

Automatic counts usually record total traffic flow but can also be used to classify vehicles.
Automatic counters comprise a counting device connected to a sensor that is mounted in or on
the road and which produces a signal every time a vehicle passes over it. They can be either
permanent or temporary installations and their main advantage is that they can record data over a
long period at a relatively low operational cost.(Overseas Road Note 40).

5.2 Purpose of Traffic Counts:

 For design purposes.

 To calculate road user costs.
 For road classification.

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 For environmental appraisal.

 For cost-benefit analysis.

The Annual Average Daily Traffic (AADT or ADT) is the most widely used statistic to indicate
the level of traffic on the road. For structural design purposes the highest traffic loading in one
direction is required and so care is always required when interpreting ADT figures. Information
from classified traffic counts also help in planning axle load surveys. For instance, the
information on commercial vehicle flows per hour throughout the day will indicate whether it is
possible to weigh all commercial vehicles. Types of automatic counters are the pneumatic tube
systems, buried loop systems and piezo systems.

5.3 Location of Survey:

 The location of the survey depends on the type of road being surveyed and its location.
The site should be chosen primarily because of the need to determine the traffic level on
that route.

 Access to facilities such as water, food and toilets should also be considered in the choice
of the site.

 The health and safety of the survey staff should be assured within the survey location.
This includes avoiding hazardous traffic sites and other problem areas such as location
within sharp curves.

5.4 Staffing and Equipment:

The number of staff required will depend on the traffic flows at the particular site, the duration of
the surveys, and the complexity of the data required. For most roads, at least two observers with
separate count forms are needed all the times; one for each direction of traffic. Some roads
require staff to work in shifts, up to three or more. This work type can be tedious and short shifts
of up to four or six hours are recommended. Additional facilities and equipment needed include:

 Shelter
 Night time lighting

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 Food and water

 Access to toilet facilities
 Survey sheets
 Clipboard, pens and pencils
 Alarm clock (to notify shift changes). (Overseas Road Note 40).

5.5 Variation in Traffic Flows and Accuracy of Counts.

Traffic counts carried out over a very short time period can produce large errors because traffic
flow often have large hourly, daily, weekly, monthly and seasonal variations. These variations
are described below.

5.5.1 Hourly Variation:

Fluctuations in the flow of traffic occur throughout the day. There are peak hours where traffic
movement is very high such as in the morning when people travel to work. Other times such as
night times have low traffic volumes. Traffic counts are usually conducted for 12, 16 or 24-hour
time periods. For periods less than 24 hours, not all the traffic may be counted and it is therefore
sometimes necessary to scale up the counts of shorter duration according to the ratio of the flows
obtained in 24 hours.

5.5.2 Daily and Weekly Variation:

Traffic varies throughout the week. For example, the number of commercial vehicles plying the
road reduces significantly on weekends. In rural areas, the traffic flows can be high on weekends
but this is reversed in urban areas. Day to day traffic flows tend to vary more than the week to
week flows over the year. Hence large errors can be associated with estimating average daily
flows from traffic counts which exclude the weekend or only of a few days duration. Thus a
survey of seven consecutive days is optimal and surveys beyond this do not increase the
accuracy significantly.

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5.5.3 Monthly and Seasonal Variation:

Traffic flows vary from month to month and from season to season usually. The seasonal
variation can be quite large and is caused by many factors. For example, during periods of
harvests, traffic flow increase significantly and the reverse occurs at the start of the rainy season.
To reduce the error in the estimated annual traffic data caused by seasonal traffic variations, it is
necessary to repeat the classified traffic count at different times of the year. Weekly traffic
counts repeated at intervals throughout the year will provide a much better estimate of the annual
traffic volume than a continuous traffic count of the same duration.

Practical Assignment:
A practical traffic count survey was organized by Mr. Nathan Amoako on the Tema motorway
for a week, between 7am to 5pm to acquaint myself with the traffic count studies and procedures

5.6 Axle Load Survey

An axle load survey is carried out to determine the axle load distribution of the heavy vehicles
using the roads. Axle load studies sufficiently accurately estimate the current traffic loading
essential for an appropriate pavement design. It is overloading and because of the unknown
proportion of the vehicles that may be partially loaded.

5.6.1 Reasons for Axle Load Studies:

 For pavement design.

 For future projection.
 For planning purposes.
 For maintenance purposes.

There are three main ways of measuring axle loads, using:

a. A fixed weighbridge;

b. Portable weighpads;

c. Weigh-in-motion equipment.

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5.6.2 Fixed Weighbridges:

These are large weighing platforms used for vehicle and axle load regulation and certification.
They are located at sites on highways and other major roads. Administration of these
weighbridges in Ghana is done by Ghana Highway Authority. Advantages of permanent
weighbridges are that they are manned by trained staff and they are safer to operate since the
environment is controlled.

5.6.3 Portable Weighpads:

These are small loadometers used either singly or in pairs to measure the individual wheel or
axle load of a vehicle. They are not fixed but can be moved from one location to the other. There
are different types which vary in design such as hydraulic, hydrostatic, strain gauge or dial or
digital. Portable weighpads have got the advantage of being easily set up anywhere and being
relatively cheap. However, weighing at the road side is not as safe as an off-site location. Traffic
is almost certainly disrupted and weighing is slower than for a fixed pad.

5.6.4 Weigh-in-motion:

Weigh-in-motion systems use a weight sensor set into the road surface so that all vehicle axle
loads are recorded at low (or sometimes normal) traffic speeds. This system is capable of giving
the most complete information but is less accurate and often the most expensive of the three
options. Care must be taken with its installation to minimize errors.

5.3 Planning a Survey:

An axle load survey needs to be carefully planned in order to achieve and maintain high safety
levels, to obtain accurate data with a minimum of traffic delays, and to keep costs to a minimum.
Preparatory work needed in advance of the survey include:

a. Locating a suitable site for the survey which has no corrugations, is level, is not located
within a curve.

b. Informing the general public on the impending survey.

c. Getting the assistance of the police to stop vehicles.

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d. Get road signs and traffic cones to inform and warn traffic of the exercise.

e. Three technicians to assist the operations. One person speaks to the driver, another directs
the vehicle and one is located behind the vehicle.

f. The start and end time should be noted.

Some of the necessary materials for the survey are;

 Data collecting forms.

 Pencils/ pens.

 Clip boards.

 Portable weighpads, etc.

The vehicles are directed to position each axle on the weighpads. Readings for each individual
axle is recorded and this is done for all the axles being weighed.

5.8 Analyses of Results:

The main aim of an axle load survey is usually to determine an average equivalency factor (EF)
for each type of vehicle in the survey. The Equivalency Factor represents the average damaging
effect of a vehicle on the pavement and is expressed as the number of standard axles (80KN) that
would cause the same amount of damage. To find the average EF, the EF for each axle of every
vehicle is calculated and summed up to obtain the EF for each and every vehicle.

The damaging effect of axles on pavements is expressed by Liddles Equation:

( )
n
L
D=
8.16

n = damaging factor and it is a figure between 4 – 6. A factor of 4.5 is used in Ghana.

D= Equivalent Standard Axle.

L = Load in tonnes.

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For highly accurate results, the standard axle used should conform to the axle configuration of
the vehicle in question. Here are some standard axles and corresponding axle configuration:

Standard Axle Axle Configuration

6.6 tonnes Single wheel, single axle.

8.16 tonnes Dual wheel, single axle.

7.15 tonnes Dual wheel, tandem axle.

7.63 tonnes Dual wheel, triple axle.

5.6 Errors in Axle Load Surveys:

Listed below are some of the most common errors made during axle load surveys and the
corresponding data analysis. Such problems should be avoided in axle load surveys.

1. Not recognizing the influence of the survey itself on the axle load distribution and vehicle
flows.

2. Survey too short.

3. Weighpads or weighbridges not accurately calibrated before use.

4. Not distinguishing between the directions of travel.

5. Assuming that all roads carry a similar distribution of axle loads.

6. Not clearly stating whether data are for wheel loads or for axle loads.

7. Not converting wheel loads to axle loads.

8. Not weighing or accounting for empty vehicles.

9. Inputting incorrect data.

10. Calculating the average EF for a vehicle type using the average axle load.

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Practical Assignment:
A practical axle load survey was organized by Mr. Nathan Amoako at the Tema Axle Load
Station for 2 days. A sample of the results is shown in the Appendix .

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