Viscoelastic Response of Reflective Cracking under Dynamic Vehicle Loading in Asphalt Concrete Pavements

Abstract

In order to investigate the mechanics of reflective cracking in asphalt concrete pavements under dynamic vehicle loading, a three-dimensional finite element model was created in ABAQUS. The viscoelastic behavior was described with a prony series, which was calculated through non-linear fitting to the creep test data obtained in the laboratory. Based on viscoelastic theory, fracture mechanics and dynamic finite element methods, three modes of cracking stress intensity factors were used as fracture evaluation parameters. A dynamic simplified rectangular dual wheel loading was used to simulate the vehicle loading. Finally, the mechanistic response of pavement reflective cracking under different vehicle speeds, various damping factors and different cracking lengths was analyzed. The results indicated that increasing either the vehicle speed or structural damping factor could decrease the maximum values of the fracture parameters, while the cracking length had a great effect to the variation of the stress intensity factors. The initiation and development of reflective cracking under the load path were mainly affected by mode I and II stress intensity factors, while reflective cracking along the edge of the pavement was affected primarily by mode II and III stress intensity factors. Therefore, by improving the traffic environment to enhance the vehicle speed and modifying the components of the pavement material to make the damping factor larger, the development of reflective cracking could be effectively delayed and the asphalt pavement service life extended.