排水沥青路面空隙变化下的动力响应分析

Dynamic Response Analysis of Void Variation for Drained Asphalt Pavement

分析排水沥青路面在渗流和动荷载联合作用下的动力响应过程,提高排水路面行车安全.通过设计物理实验获取沥青混合料参数,建立排水沥青路面数值分析模型,分析路面内部空隙变化下的排水沥青路面超孔隙水压力和特征应力的时程变化情况,并与普通密级配沥青混凝土路面进行对比.结果表明:在行车荷载作用下,排水沥青路面内出现超孔隙水压力的正、负交替变化,在面层与基层交界面处最为严重,排水面层和防水层渗透性的差别会导致局部超孔隙水压力突变.排水沥青路面排水面层内的超孔隙水压力远小于密级配沥青混凝土面层和其他结构层,排水面层中竖向应力较密级配沥青面层大,且超孔隙水压力的消散速度更快.

To analyze the dynamic response process of drained asphalt pavement under the combined action of seepage and dynamic load,based on the physical experimental and the porous medium theory,a three-dimensional finite element model of drained asphalt pavement is proposed to analyze the changes of ultra-void water pressure and characteristic stress with the combined action of seepage and dynamic load.It is also compared with dense graded asphalt concrete pavement.The results show that under the combined action of seepage and dynamic load,there are positive and negative alternating changes of ultra-void water pressure in drained asphalt pavement.It is the most serious at the interface between the surface layer and the base layer.The difference in permeability between the drainage surface layer and the waterproof layer will lead to the sudden change of local ultra-void water pressure.The ultra-void water pressure in the drainage surface layer of drainage asphalt pavement is much less than that of dense graded asphalt concrete surface layer and other structural layers.The vertical stress in the drainage surface layer is larger than that of dense graded asphalt surface layer,and the dissipation speed of ultra-void water pressure is faster.