高速公路上坡路段半刚性沥青路面的三维有限元分析

运用三维有限元方法,分析了不同道路纵坡下路面结构层层底最大拉应力、层底最大剪应力和土基最大压应变的变化规律,以及上坡路段在不同超载率、路面摩擦系数和温度状况下各主要路面结构力学指标的变化情况,并提出了相应的防治对策。分析结果表明,道路纵坡改变只对面层所受拉力有影响,更易使面层产生开裂;各面层都是剪应力作用的主要集中区域;超载率、路面摩擦系数和温度对上坡路面结构受力都存在不同程度的影响,汽车超载的影响最大。因此,应尽量提高沥青混合料面层的抗拉强度和抗剪强度,并严格限制上坡车辆超载。

Three Dimensional Finite Element Analysis of the Semi-rigid Asphalt Pavement of Upslope in Expressway

The regularity of maximum tensile stress,maximum shear stress of the pavement,and the maximum compression strain of the subgrade at different slope is presented by FEM.Then the variation of the main mechanical index under the vary conditions of overload factor,friction coefficient and temperature is analyzed and the corresponding countermeasures are presented.The result shows that the tensile stress of surface is affected by slope change and it makes the surface easier for cracking.The surface shear stress is a major focus of the pavement structure.It also shows that overload factor,friction coefficient and temperature affect the stress of pavement diversely,among which the overload of automobile does the most.So it should enhance asphalt mixture layer tensile and shear strength,and strictly control uphill vehicle overloading.