On Dynamic Pore Pressure in Moisture Damage of Asphalt Pavement

For studying the accelerating role of dynamic pressure in moisture damage of asphalt pavement, based on fast Lagrangian finite difference method and Biot dynamic consolidation theory, fluid-solid coupling analysis was done considering asphalt mixtures as porous medium. Results revealed that development and dissipation of the dynamic pore pressure are coinstantaneous and this makes the positive and negative dynamic pore pressure and seepage force both alternate. The pumping phenomenon of saturated asphalt pavement under moving vehicle load was proved. The dynamic pore pressure increases with vehicle velocity. Effective stress and deflection of pavement all decrease due to the dynamic pore pressure. The maximum dynamic pore pressure occurs at the bottom of the surface course. So it's suggested that a drain course should be set up to change the drained condition from single-sided drain to both-sided drain, and thus the moisture damage can be limited effectively.