不同裂缝形式下沥青混凝土路面内孔压变化规律研究

Study on pore water pressure of asphalt concrete pavement with different cracks

为了研究车辆荷载作用下沥青混凝土路面中裂缝孔压的变化规律及其对路面质量的影响,基于Biot固结理论及裂隙渗流和流固耦合理论,利用COMSOL Mutiphysics建立沥青混凝土路面结构三维流固耦合模型。对比当车辆移动荷载经过时无裂缝、横向裂缝、纵向裂缝和交叉裂缝四种路面情况下沥青混凝土路面的孔隙水压力增长、消散规律和路面形变。数值分析结果表明:相对于横向裂缝,纵向裂缝的存在更有利于孔隙水压力的消散;横向裂缝和交叉裂缝存在时孔隙水压最大,从而加剧了路面的水损害;裂缝对路面形变无显著影响。

Based on Biot consolidation theory,fluid flow through fractures and fluid-solid coupling theories,a three-dimension model of concrete pavement is established in COMSOL Mutiphysics software to study variation of the pore water pressure through fractures and whether it can exert bad effects on the pavement under the vehicle loads condition. The displacement of pavement,variation trend and dissipating regular of pore water pressure are compared while vehicle passed the reference line of the road under four different pavement conditions,including non-crack,horizonal crack,perpendicular crack and cross crack. The results of numerical analysis show that perpendicular crack has a positive effect on the dissipation of pore water pressure compared to the horizonal one. Pore water pressure reaches peak on the pavement full of horizonal and cross cracks,which damage the road itself to some extent. Fractures have no significant effects on the displacement of the pavement.