基-面层局部黏结失效对半刚性基层沥青路面拉裂破坏的影响分析

Analysis of the Influence of Local Bond Failure of Base-surface Layer on Crack Failure of Semi-rigid Base Asphalt Pavement

为了研究基-面层间局部黏结失效对沥青路面拉裂破坏的影响,考虑重载的作用,采用ABAQUS建立三维弹塑性模型对不同黏结失效区域大小和不同黏结强度下引起半刚性基层沥青路面拉裂破坏的竖向变形和层底拉应变进行分析.结果表明:黏结失效区域面积对竖向变形的最大值和两车轮荷载中心竖向变形差值有显著影响,重载只影响竖向变形值的大小不改变其分布规律,层间黏结强度对竖向变形的影响可以忽略.随着基-面层黏结失效面积的增大沥青路面的拉裂破坏点从中面层底向下面层底过渡,重载不仅改变塑性拉应变的数值同时也影响其分布规律,黏结强度对下面层底拉应变的影响极大,对其他层的影响可以忽略.

In order to study the influence of local bond failure between base and surface layer on the tensile crack failure of asphalt pavement,and considering the effect of heavy load,ABAQUS was used to establish a three-dimensional elastic-plastic model to analyze the vertical deformation and tensile strain at the bottom of asphalt pavement with semi-rigid base under different bond failure areas and different bond strengths.The results show that the area of bond failure zone has a significant influence on the maximum value of vertical deformation and the difference of vertical deformation between two wheel load centers,while heavy load only affects the value of vertical deformation without changing its distribution law,and the influence of interlayer bond strength on vertical deformation can be ignored.With the increase of bond failure area of base-surface layer,the tensile crack failure point of asphalt pavement transits from the bottom of middle surface layer to the bottom of lower surface layer.Heavy load not only changes the value of plastic tensile strain,but also affects its distribution law.Bond strength has a great influence on the tensile strain at the bottom of the lower layer,and its influence on other layers can be ignored.