The performance of pavement rehabilitations under accelerated loading - the Callington ALF trial

The Department of Road Transport in conjunction with the Australian Road Research Board has conducted a series of full scale pavement tests using the ARRB Accelerated Loading Facility on the South East Highway near Adelaide. The aim of the trial was to test the relative performance of alternative forms of asphalt rehabilitation. An existing section of distressed pavement was repaired using a variety of thin overlay treatments and various thicknesses of asphalt reinstatement. A total of 17 loading experiments were conducted. The relative performance of the treatments was measured in terms of their resistance to surface deformation and crack propagation. Preliminary analysis has provided a ranking of deformation resistance of all asphalt materials used with some modified binders displaying significant advantages over conventional C170 bitumen. Comparative overlay experiments clearly demonstrated a significant extension in treatment life through use of a modified binder in the asphalt overlay (A).