Fatigue Performance of Hydraulic Asphalt Concrete Under Uniaxial Constant-Amplitude Tensile Cycle Loading

The fatigue properties of hydraulic asphalt concrete (HAC) have significant impact on the impervious performance and safety of HAC embankment dam. Therefore, this study investigated the fatigue performance of HAC, including fatigue deformation, tensile failure mode and fatigue life, and proposed a model for predicting HAC fatigue life considering stress level, cycle frequency, and failure probability. For these purposes, a constant-amplitude continuous cyclic tensile test was conducted on dumbbell-shaped HAC samples at different stress levels and cyclic frequencies. The results indicated that the failure strains of HAC at different fatigue tensile loading conditions was as high as 4.6 %, which is about 2 times the monotonic tensile strain. The failure surface of the HAC sample has a larger proportion of aggregate fracture with increasing stress level and cycle frequency. In addition, the fatigue life increases significantly with the cycle frequency. Specially, at the stress level of 0.5, the maximum fatigue life can reach up to 4365 cycles with a frequency of 5 Hz, about 10 times greater than that with a frequency of 0.5 Hz. Finally, the predection model proposed based on the double logarithmic fatigue equation can accurately predict the fatigue life of HAC.