考虑静水压力作用的裂缝边坡安全性分析

Stability Analysis of Fissured Slope Considering the Effects of Hydrostatic Pressure

静水压力会触发边坡失稳,特别是对后缘大量分布裂缝的边坡而言。而当前对边坡稳定性的研究中很少考虑到裂缝和静水压力共同作用的不利影响。针对该现象,以极限分析上限法(LAM)为理论基础,结合强度折减技术针对地勘现场广泛存在的不利裂缝边坡展开研究。将不同的坡角(30°~80°)和内摩擦角(10°~30°)以及各类参数在不同程度的静水压力作用下产生的安全系数进行计算分析,并结合破坏临界滑裂面进行对比分析。结果显示:静水压力的存在会对裂缝边坡的安全系数产生较大程度的影响,最高可超过30%的折减;而考虑静水压力影响时,边坡临界裂缝的位置分布呈现一定规律。

Hydrostatic pressure can trigger the slope instability,especially for slopes with a large number fissures at top.However,the current slope stability analysis practice rarely considers the adverse effects of joint actions of fissures and the hydrostatic pressure.This paper presents the slope stability analysis results using upper bound limit analysis(UAM)and strength reduction methods on the fissured slopes.Slopes with various angles(30°~80°),various internal friction angles(10°~30°)and various amount of hydrostatic pressure in the fissures were analyzed and the factor of the safeties were reported.The results indicate that the hydrostatic pressure in the fissures can results in a large stability reduction in the slope and up to 30%of the reduction was reported.The critical location of the slip plane are similar in all instable slopes.