含软弱土层边坡稳定性分析的全局滑面自动搜索技术

Auto Searching Technique for Global Critical Slip Surface in Slope Stability Analysis with Weak Layer

提出了一种用于边坡稳定性分析的全局滑面自动搜索技术,首先采用三角网格进行了边坡土层的几何离散,然后,结合蒙特卡洛法等角/等边逐段扫描与模拟退火法,构建了全套的边坡全局临界滑面搜索扫描算法。以Fortran和Matlab为计算手段进行联合编程,采用简明Morgenstern-Price法进行了边坡稳定性分析计算。通过选用3个算例进行了算法的可靠性验证,计算结果表明:截面三角网格划分方法具有良好的适应性,能较好地对不规则层位几何形状进行离散;多段折线滑面具有较圆弧滑面更为优秀的极限滑面定位功能,其安全系数随着滑面段数的增加会逐步达到收敛;本搜索方法可不依赖于工程师经验进行多段折线初始滑面的大致范围选择,其能快速地、全自动地进行由弱到强不同复杂土质情况的边坡稳定性计算分析,并能找到全局临界滑面与安全系数。

An auto searching technique for global critical slip surface in slope stability analysis with weak layer is presented,the slope section geometry is firstly discretized into triangular mesh,Then,the Monte Carlo scanning method using constant angle/length is incorporated with the simulated annealing method(SAA)to establish the whole searching strategy for the global critical slip surface.Commercial software Fortran and Matlab are integrated to code the concise Morgenstern-Price program analyzing the slope stability.Three benchmarks are introduced to identify the program reliability.The results show that the triangular mesh has good adaptability to handle with the geometry discretization of irregular slope section.The slip surface with the feature of n-segment polyline could locate the more critical position than the circular slip surface.The factor of safety would converge as the increase of the segment number.The proposed method could quickly auto analyze the stability status of slope with different complexities from low to high,the global critical slip surface as well as its factor of safety could be found without the engineers experience to specify the range of initial slip surface.