Fatigue Performance of Cemented Materials under Accelerated Loading: Influence of Vertical Loading on the Performance of Unbound and Cemented Materials

Abstract

This research involved a performance assessment of two cemented pavement materials using the Accelerated Loading Facility (ALF) to simulate heavy axle loading. The assessment involved a number of axle loads from a standard half axle load of 40 kiloNewtons to double this load which allowed the fatigue life of the cemented materials to be determined as well as estimates of the load damage exponents. A laboratory study was conducted on the same two cemented materials to assess their strength, modulus and fatigue properties. The laboratory fatigue results generally compared well with the full scale ALF performance results and hence the laboratory test was considered useful for fatigue assessment of cemented materials. The study concluded that the load damage exponent for the two cemented materials varied between 5 and 8 and that the results did not support the current load damage exponent of 12 suggested for cemented materials in the Austroads guide to pavement technology. Further laboratory flexural beam fatigue testing was recommended to confirm this finding for a wider range of cemented materials. (a)