ABSTRACT
The primary purpose of the pavement is to reduce the stresses on the subgrade to such a level that the subgrade does not deform under the action of traffic. At the same time, the pavement layers themselves need to be strong enough to tolerate the stresses and strains to which each layer is exposed. This is the process of structural design. However good the pavement design, the condition of the road wil l slowly deteriorate with time and traffic. The long-term behaviour of the road wil l also depend on the maintenance that is undertaken. The aim is to design the road to carry traffic satisfactorily for a specified period of time without needing major structural maintenance (renewal).
