层间接触对沥青路面粘弹性动力响应影响研究

Influence of Interlayer Contact on Viscoelastic Dynamic Response of Asphalt Pavement

为分析沥青面层材料粘弹特性及路面各层间接触条件对沥青路面动力响应的影响,基于解析的方法,开展了层间非完全连续沥青路面粘弹性动力响应的求解工作.采用修正的Burgers模型定义沥青面层材料的粘弹性本构关系,考虑沥青路面层间接触条件,在车辆荷载作用下,建立沥青路面的理论计算模型;通过Laplace-Hankel积分变换将偏微分方程组转化为常微分方程组并对问题进行求解;采用转换矩阵表征层间接触条件,求得层间非完全连续沥青路面粘弹性动力响应的解析表达式.从沥青路面实例计算结果发现:修正的Burgers模型中的瞬时弹性模量参数E11是对弯沉计算结果影响最大的因素之一,路表弯沉随E11的增大呈下降趋势,特别是当E11较小时,这种趋势尤为明显;沥青混合料本构模型中的粘弹性修正系数B和黏性参数η2是影响路面路表弯沉计算结果的另两个重要因素,并且B和η2对弯沉峰值出现时间的影响具有相反的趋势;层间的非完全连续条件对沥青路面动态弯沉计算结果影响较大,并以面层与基层间的非完全连续对弯沉计算结果影响最为显著.

In order to analyze the viscoelastic properties of the asphalt pavement material and the influence of contact conditions between pavement layers on the dynamic response of asphalt pavement,the viscoelastic dynamic response of the asphalt pavement with incomplete interlayer continuity is solved based on the analytical method.The viscoelastic constitutive relation of asphalt pavement material is defined using the modified Burgers model,and the contact conditions between asphalt pavement layers are taken into account to bear the vehicle load.In this way,the theoretical model of the asphalt pavement is established.The partial differential equations are transformed into the ordinary differential equations via Laplace-Hankel integral transformation to solve the problem.The transformation matrix is used to characterize the contact condition between layers,and the analytical expression of viscoelastic dynamic response of asphalt pavement with interlayer incomplete continuity is obtained.From the results of the calculation examples,it is found that the instantaneous elastic modulus E11in the modified Burgers model is one of the most influential factors for the deflection results.The calculated surface deflection shows a decreasing trend with the increase of E11,especially when E11is small.The viscoelastic correction coefficient B and the viscosity parameter η2in the modified Burgers model of the asphalt mixture are two other important factor affecting the surface deflection results.It shows that the influences of B andη2on the time of peak deflection are opposite.The incomplete continuity condition between layers has great influence on the calculated dynamic deflection,with the incomplete continuity between pavement layer and foundation layer being the most influential.