Strain Dynamic Response of Asphalt Pavement on Steel Deck Bridge with Field Loading Test

Abstract:

In order to obtain the actual mechanical response of asphalt pavement of steel deck bridge, a field loading test was carried out on Changji East Road Bridge in Shanghai, a steel bridge of the pavement with stone mastic asphalt and epoxy asphalt as the upper and the lower layers respectively. Test results show that the maximum strain appears at surface, where the pavement is the easiest to be damaged. The dynamic response of longitudinal and transverse strains under two loading conditions (uniform velocity and brake) was analyzed in different layers, and the response trends at the same measurement point had little discrepancy. Longitudinal dynamic strain alternated in tension compression cycles and fluctuated, while transverse strain merely fluctuated. With the increase of the depth and the speed, the dynamic strains decreased according to the decrease of the axle loads. The transverse strain was greater than the longitudinal value, and the amplitude of the former was more sensitive to the influence factors than that of the latter. Sensitivities of dynamic strains and their amplitude to axle load and vehicle speed decreased from top to bottom. The differences between dynamic and static strains existed different rules in three layers. The results can be applied to the structure design or material selection of asphalt pavement on steel bridge.