水力作用下顺层岩质边坡稳定性分析

Analysis of stability of rock bedded slope under hydraulic pressure

通过对顺层岩质边坡中地下水力作用进行分析,认为地下水力作用主要为沿结构面分布的裂隙水压力和拖拽力。分析了滑动破坏中的控稳优势结构面,认为该面上的张裂隙静水压力、滑动面扬压力以及拖拽力的大小均取决于后缘张裂隙的充水高度。将典型岩石边坡进行简化假设,利用简化后的边坡水力学分析模型,推导出边坡稳定系数和决定边坡稳定性的张裂隙充水临界高度的表达式。选取实际边坡进行分析和计算,验证了公式的合理性,结果表明地下水作用下边坡稳定系数的降低主要与静水压力有关,而渗透力的影响很小。

By analyzing the effect of groundwater water on rock bedded slope,it is found that the stresses of groundwater mainly act as fissured water pressure and drag force on structural plane.And through the analysis of the dominant joint plane controlling the stability in sliding failure,this paper holds that the fissured hydrostatic tension on this plane,the pressure on sliding surface and the drag force are all decided by water filling at the back edge of the fissure.In this paper,also on the assumption that typical rock slope samples are simplified,making use of the simplified hydraulic model of slopes,two numerical expressions are presented.One is about the slope stability and the other is about the critical height of water filling in cracks which decides the slope stability.Based on the analysis and calculation of actual slopes,the proposed formula is proved to be reasonable.It is also concluded that the decrease in slope stability under the influence of groundwater is mainly related to hydrostatic pressure instead of its penetration.