ABSTRACT
ABSTRACT: A laboratory investigation of the effects of different multiple axle group loads on the fatigue performance of a cemented material was conducted. The study made use of a preexisting laboratory test process for assessing the flexural modulus and fatigue characteristics of cemented materials, extending it by simulating multiple axle loads (single, tandem, triaxle and quad-axle groups) using a range of load pulse shapes designed to broadly simulate truck axle groups. The study developed relationships between fatigue performance and initial strain level for each simulated load shape. The flexural modulus of the cemented material used was found to be highly variable, with the majority of samples between 15 000 and 22 000 MPa. The variable nature of the samples hampered the drawing of conclusive findings. A relationship was determined between the fatigue life, the initial strain level and the combination of the peak load applied and the load type.
