Research on pore pressure within asphalt pavement under the coupled moisture-loading action

The coupled moisture-loading action is the primary factor of initial failure for asphalt pavement. At first, porous media theory was used to describe asphalt pavement in the environment. Then, transient dynamic analysis of axisymmetric finite element method was employed to calculate the pore pressures at different times within saturated asphalt pavement based on saturated porous media theory. Finally, the pore pressure variations between different permeabilities, vehicle speeds and loadings were analyzed. The result indicates that the dynamic action of vehicle makes the pore pressure within pavement structure have wave characteristics. It also shows that the cycling action of positive and negative pore pressure is the primary inducement of the asphalt film failure, and high vehicle speed and overloading will accelerate the reduction of pavement performance when moisture exists in pavement structure.