沥青路面荷载型裂缝的剪切机理与成因分析

The Analysis of Shear Mechanism and Formation of Asphalt Pavement Load Cracking

越来越多的研究表明沥青路面轮迹带附近的荷载型裂缝与沥青面层内较大的应力水平尤其是剪应力有着直接的关系,为了探讨其破坏机理及力学成因,基于弹性层状体系在考虑水平荷载作用下进行半刚性基层路面剪应力有限元分析,分析沥青面层内剪应力分布规律,剪应力峰值变化情况,并对剪应力和拉应力进行对比分析。结合荷载型裂缝产生位置、深度等特点可以认为其产生的主要原因不是拉应力而是剪应力,对进一步研究荷载型裂缝的破坏机理、发展规律有一定的指导意义。

More and more evidences showed that asphalt pavement load cracking along wheelpath has direct relation to the high stress level in the asphalt pavement especially the shear stress.For the purpose of studing the shear mechanism of asphalt pavement load cracking,this paper based on elastic layered system make finite element analysis of semi-rigid asphalt pavement shear stress.The shear stress distribution regularities and maximum of shear and its direction are achieved.The locations of the shear stress and tensile stress were compared with load cracking characteristics and the maximum stress was compared with stress strength as well.The analysis shows that the major reason of asphalt pavement load cracking is shear stress not tensile stress.The research conclusions have certain guiding significance for the further study of asphalt pavement load cracking.