Chapter 9
Pavement Maintenance
9.1 Introduction,
Highway pavements, once constructed, will not last forever. After a time, signs
of wear will appear. These signs include cracking, rutting and polishing of the
road’s surface. A point will arrive where the wear and tear is at such an advanced
stage that the integrity of the pavement and hence the standard of service pro-
vided by it has diminished. Maintenance is required at this point to prolong the
highway’s useful life. Loss of skidding resistance and loss of texture are forms
of deterioration eventually suffered by all highway pavements.
In order to carry out the maintenance in as cost-effective a manner as possi-
ble,a logical coherent procedure must be adopted in order to select the most
effective form that the maintenance should take, together with the optimum time
at which this work should be undertaken. Minor maintenance may be sufficient
to maintain the required standard of service for the motorist. However, in situ-
ations where major structural strengthening is required, a comprehensive struc-
tural investigation is vital in order to assist in the completion of the required
detailed design (HD 30/99) (DoT, 1999).9.2 Forms of maintenance,
For bituminous roads, maintenance can be either minor or major. Minor main-
tenance takes the form of patching. It allows defective materials, particularly
those in the surface courses of the pavement, to be replaced. If done properly,
it can restore the stability and riding quality of the surface, arresting its deteri-
oration and extending its serviceable life. It is an integral part of highway main-
tenance and makes sound economic sense.
Patching can remedy the following defects: Substandard drainage or some other problem related to the subgrade which
will cause the failure of the pavement’s foundation
The aging of the bituminous surface, causing its break-up with the conse-
quent formation of potholes and areas of crazing