TAH-9 PROJECT

ROAD MAINTENANCE GUIDELINES

PREFACE
The following guidelines is a result of the efforts taken by the PLANET SA and ADK
consultants to present a detailed presentation of how to maintain the integrity and operability of
the road network within the TAH-9 corridor western part .
Much of it is aligned to the directives of the relevant SANRAL Manual.
The importance of road maintenance has been underestimated in many South African Countries .
For every dollar not invested in road maintenance 2-3 dollars are lost .
So poorely funded road maintenance schemes have a great negative impact in socioeconomic
factors in the area. The relevant road authorities in the three beneficiary countries (Angola , DRC
and Zambia) should give a chance to small enterprises to pop up along the corridor by assigning
small contracts in road maintenance and helping those enterprises gain technology know-how
and the ability to develop themselves.

INTRODUCTION
In spite of their importance, most roads in the TAH-9 corridor western section are poorly
managed and badly maintained. The three beneficiary countries Angola, DRC and Zambia to a
lesser degree have systematically disregarded issues of road routine and periodic maintenance.
The lack of maintenance is the primary reason for erosion observed in many of the existing roads
in the corridor.(see Chapter 4 Interim Report Visual Reconnaissance / Existing Road
Conditions)
The guidelines focus in providing guidance and assistance to relevant road authorities of the
involved countries to:
 appreciate the various aspects of road management, encounter safety and environmental
issues
 identify problems that need attention
 Select suitable methods of action or repair
 Set priorities to actions needed
Pavement structures, materials, traffic and climate are all important variables that affect the
actions required in response.
In addition a balance is required between a safe, efficient road network and responsible
environmental practice. For these reasons there are no absolute solutions. The aim of these
guidelines is thus to give general directions and help the Road Authorities of the beneficiary
countries to make logical decisions and apply sensible and appropriate methods to carry out the
necessary maintenance actions.
2. ROAD MANAGEMENT & INSPECTION PRACTICES
The Site Management Contractor assigned a routine road maintenance contract , provides
assistance in the management of the corridor road network by monitoring the performance of
the roads and alerting Governmental Road Authorities to matters like illegal practices, road
safety issues, road performance and encroachments.
The contractors should inspect the site frequently so that problems are identified, the causes
investigated and assessed and the actions required identified and carried out in time. Inspections
should also be carried out at night in order to view potentially hazardous locations, signs and
markings, and in adverse weather conditions to assess drainage and the performance of the
elements , like pavement ,signs and roadmarkings, under these conditions.

Inspection at dusk
Obvious problems should be noted as soon as they become evident and in serious situations
reports must be submitted immediately.
A list containing the various aspects to be checked , the frequency of the inspections, previous
inspection date and due date of next inspection should be drawn up.
The following requirements contained in the engineering services contract must be taken into
account in drawing up the check list:

Road Elements Frequency Road Elements Frequency

Signs Yearly Fill & Cut According to
instabilities problem
seriousness
Roadmarkings Yearly Settlements Weekly
Guardrails Monthly Illegal access Monthly
Structures Yearly Fencing Monthly
Flexible pavement Sixmonthly Illegal Signage Monthly
condition
Rigid pavement Sixmonthly Drainage Monthly
condition

2.1 PAVEMENT INFORMATION

2.1.1 Pavement structure

A basic knowledge of the road pavement structure along the corridor is of utmost importance.
Existing pavement characteristics should be known i.e. type of surfacing (any reseals/overlays) ,
base , subbase thickness and age of pavement.

2.1.2 Pavement condition

The Site management contractor should know the overall condition of the various sections of the
route and rates of deterioration. This information is crucial for the decision on what actions need
to be taken particularly with regard to the extent and prioritisation of repairs.
In case of serious damages such as where a road has widespread crocodile cracks together with
extensive rutting ,the Governmental Road authorities should be notified immediately.With this
knowledge, the Authorities may then need to alter their network strategies to give priority to a
special maintenance project on this particular section.
Information such as pavement deflections can also give indications of potential weak areas.

Pavement at end of economic life

2.1.3 Rates , Quantities availability of materials

Knowing rates and quantities is a must not only to control expenditure on the project but also to
test the cost implications of various repair methods. If more than one repair method is possible
then cost should be a key factor to be weighed against other issues such as materials availability,
weather, traffic and constructability, in making the right choice. Accurate estimates of quantities
and the payment items to be
used must be specified in the contract Job description .
The Site management contractor should have a good idea of which materials are available, their
costs and their source locations. Calling for minor hot asphalt repairs for example in an area
remote from an asphalt plant is not practical unless the Contractor has the capability for on-site
manufacture of hot asphalt. Prior to the use of material from a borrowpit or quarry, the status of
the material source must be clarified in terms of approval by a certified materials laboratory .

2.1.4 Maintenance problems and methods of addressing them

Problems and causes not correctly identified result in unnecessary or wrong repair methods
being used. The guidelines provide information to help the Site management contractor to
recognise the common problem areas and have an appreciation of possible causes.
Since the problem has been correctly identified it is equally important to select an appropriate
treatment. Due to the variety of situations it may be possible that more than one treatment should
be considered .
Pavement maintenance is a specialist field requiring appropriate knowledge and years of
experience to accurately identify and remedy pavement defects. Should there be a significant
shortage of these skills in the corridor then every effort should be made to develop this field. To
maintain a high standard of work, the site management contractor should be on the look out
for subcontractors and/or their employees who demonstrate potential and interest in this field.
Such individuals once evaluated may be trained and developed further.

SETTING PRIORITIES
It is likely that road network maintenance will always be faced with budgetary
constraints and strong competition from other sectors. As a result it is vitally important that
maintenance is cost effective and that the work is prioritised in situations of limited funding.

The three major objectives of routine maintenance are to:

 provide a safe and acceptable level of service for the travelling public
 prolonging road life and postponing day when renewal will be required
(asset preservation).
 ensure that the road environment is attractive (aesthetically pleasing).
Top priority is to keep the road safe at all times. Situations which may result in accidents or
cause damage to vehicles should be handled first. Generally this will mean that a failed road
surface will be given top priority in a maintenance scheme .
However, other situations such as
 damaged guardrail projecting into the carriageway
  a slippery road surface due to spillage of some material
 poor visibility due to smoke from a fire in or close to the road reserve
 a deep pothole that is dangerous for the traffic especially at night
 the proximity of schools and the presence of pedestrians all need to
be assessed because of the risk to the travelling and general public.
Secondary issues such as smooth surfaces and rutting also pose a safety threat. Because these are
often widespread the risks are less easy to quantify.
Actions like surface texture correction or rutfilling over widespread areas fall into the category of
periodic maintenance.
Any situation where significant amounts of water can get into the pavement is critical and, if left
unattended, will result in rapid deterioration of the pavement structure.
Such situations could arise from :
 subsurface seepage or springs (mainly in cuts or low lying areas)
 shallow side drains in flat grades
 water ponding on the road surface or on the shoulders. Unfortunately these
considerations cannot be assessed in isolation but should be addressed in a routine
maintenance scheme .
For roads with extensive pumping, crocodile cracks and rutting which are scheduled for
rehabilitation within the next two years normally the riding quality under these circumstances is
acceptable and, provided the cracking does not develop into extensive failures, a reasonable level
of service will be possible with little or no maintenance action up to the time of rehabilitation.
Road Department Agencies should be informed that the particular section of road is in poor
structural condition. If no changes can be made to the periodic maintenance programme certain
interim measures could prevent severe deterioration of the pavement over few years. These
measures could include actions to reduce water infiltration such as a geofabric crackseal,
roadpatch or a modified emulsion slurry depending on the extent of the problem.
Other maintenance actions such as litter removal, grass cutting, replacing signs and minor repairs
on guardrails and fencing are not as important as the actions listed above. However each one
should be judged on the circumstances of the contract. In dry season at a time of high fire risk
grass cutting could substantially reduce such a risk. Guardrails in poor condition on a dangerous
curve where accidents occur frequently hide a high risk to traffic.
On certain routes frequent single vehicle accidents are attributed to driver fatigue. Provision of
rest areas encourage the drivers to break their journey.

High priority pavement failure