During the 1980s there was an increasing trend in the occurrence of fatigue cracking of asphalt surfacings as the predominant failure mode on heavily trafficked pavements in South Australia. Whilst the introduction of mechanistic design methods had helped to provide an improved understanding of the high sensitivity of asphalt surfacing life to the stiffness and fatigue properties of the asphalt materials, it was recognised by the late 1980s that there was a need to validate these design inputs for materials used in Australia because of their influence on design life and pavement cost. The introduction of new types of modified binders posed an additional problem in that they did not conform with existing experience and it was difficult to assess the required thickness and conditions under which they are cost effective. Accordingly, there was seen to be a need to derive design criteria under field conditions and establish by direct field correlation the relative benefits of different material types. Between July 1988 and October 1989 the South Australian Department of Transport and ARRB Transport Research conducted a series of full-scale pavement tests using the Accelerated Loading Facility (ALF). Testing was carried out on a section of distressed pavement that had been rehabilitated by a variety of asphalt treatments. Over 3.3 million loading cycles were completed during 17 experiments on different asphalt rehabilitation configurations. This report summarises the results of the trial. (a).
