Fatigue and rutting performance of conventional asphalt and bitumen-rubber asphalt under accelerated trafficking.

Abstract

The Californian Department of Transportation commissioned a pilot project to evaluate the potential of the Heavy Vehicle Simulator (HVS) for conduction pavement studies. The effect of channelisation of traffic on the rutting behaviour of a continuously-graded asphalt overlay was investigated. Secondly, the cracking behaviour of a 75 mm thick continuously-graded overlay was compared with that of a 38 mm thick bitumen-rubber asphalt overlay. A laboratory evaluation of the materials was conducted by the University of California at Berkeley. The channelisation of traffic resulted in a 100% increase in the surface rut rate compared with that under normal wandering traffic. A reduction of 50% in layer thickness is justified to obtain similar resistance to cracking if conventional asphalt is replaced with bitumen-rubber asphalt.