确定边坡的潜在滑移面及地震屈服加速度,是进行边坡动力稳定性分析的基础。该文把重力式挡墙加固边坡的潜在滑移面看作是由若干段直线组合而成的复合滑移面,并用一系列的斜线把滑体土划分为若干个三角形块体。在假设边坡岩土体服从摩尔一库仑屈服准则,根据极限分析上限定理,结合多块体速度场理论,分别计算各块体外功率与内能耗散,建立地震作用下边坡地震屈加速度的多元函数,利用数学优化方法,确定边坡地震屈加速度及其潜在滑移面分布,由此提出一种重力式挡墙加固边坡动力稳定性计算的新方法。最后通过算例进行该方法的展示,分析土体抗剪强度参数和墙体两侧粗糙度对地震屈服加速度及其潜在滑移面分布的影响。
Seismic stability analysis is based on the certain potential sliding surface and the yield acceleration of a slope. The potential sliding surface is considered to be a composite of a number of straight lines, and then the potential sliding mass is divided into a number of triangular wedges by a series of inclined straight lines. By the assumption that the slope material obeys a Mohr-Coulomb criterion, the upper bound method and multi-wedge translations mechanism are used to calculate the rate of external work and the rate of energy dissipation for each triangular wedges, respectively, and so to establish the multivariate function to calculate the yield acceleration of reinforced slope. The yield acceleration and the corresponding potential sliding surface can be obtained by optimization. Thence, a new approach is presented in this study to consider the seismic stability of gravity retaining walls. At last, an example is shown to illustrate the method. The influence of shear strength parameters and wall roughness to the yield acceleration and potential sliding surface are analyzed.