层间弱结合程度及其范围对沥青面层应力的影响

The influence of different inter-layer strength and regions on the stress of asphalt surface course for cracking semi-rigid base

为了深入研究基-面层层间结合状态对半刚性基层沥青路面反射裂缝的影响,采用Ansys,开展了二维有限元计算。以接触对长度和摩擦系数分别表征层间弱结合范围和结合程度,分析了不同荷载条件下基-面不同层间接触条件对沥青下面层层底拉应力和剪应力的影响,提出了竖向对称荷载、竖向偏载、水平力及温度应力单独作用时适宜的层间结合条件。研究结果表明:竖向对称荷载和水平荷载单独作用或两者联合作用下,基-面层层间结合得越紧密,其弱结合范围越小,对路面结构越有利;竖向偏载和温度应力单独作用或两者联合作用下,基-面层层间结合越弱,对路面结构越有利;除了频繁出现水平力或者水平力较大路段以外,没有必要要求半刚性基层沥青路面的基-面层层间处于完全连续状态,但需要相关试验和工程进行进一步的验证。

In order to study the influence of the copulation state between laminates on reflection cracks of semi-rigid asphalt pavement, a 2--D finite element visual software was used to study the stress variation of asphalt pavement with different inter-layer conditions between semi-rigid base and surface course whose weak-binding areas and weakbinding degrees were represented by the length of contact pairs and friction coefficient by appling various load forms.Then,appropriate inter-layer contact conditions under independent action of vertically symmetrical load forms, vertical offset load forms, horizontal force and thermal stress were put forward.The results show that better interface layer conditions and much smaller range of weak-binding region are more beneficially to the pavement structure under the independent action or coupling action of vertical symmetrical load forms and horizontal force, while under the independent action or coupling action of vertical offset load forms and thermal stress, the weaker the interlayer bonding is,the better the pavement structure is.The research shows that it is not necessary to set the inter-layer conditions between semi-rigid base and surface course to be completely continuous unless frequent emerge of horizontal force or much larger horizontal force,while further verification by relevant experiments or engineering application should be done to prove the result presentsed to us.