Rutting in Asphalt Pavement under Heavy Load and High Temperature

Rutting is one of the main distresses in the asphalt pavements, especially in higher summer temperatures and/or under heavy loads. Efforts were made in this study to investigate rutting failures on Jing-Zhu expressway in China to determine the cause and the source of the rutting. The characteristic of the rutting on each asphalt pavement layer were analyzed by surveying the rutting depth, excavating transverse profile sections, and boring samples in the typical sections of expressways where different degrees of rutting damage were observed. It was found that 60% of the rutting was generated by the asphalt middle course layer and the remaining 40% came from the other surface layers, which was consistent with the mechanical analysis of the asphalt pavement that showed that the shear stress in middle asphalt course layer was the highest in magnitude, under load or temperature. With the combination of the indoor rutting tests on the samples from a corresponding location of the road shoulders, the influence of the high temperature stability of each asphalt pavement layer on rutting was analyzed using the method of ANOVA (Analysis Of Variance). The results indicated that the stability of the middle course layer impacted the rutting development the most. Finally, the relationship between the RD (rut depth) and the DS (dynamic stability) of each asphalt pavement layer was established using a nonlinear regression method. The governing criterion for the DS at the bottom course asphalt mixture was studied and recommendation made based on regression analysis.