强降雨条件下具有张裂缝边坡临界滑动场

降雨持时较长且雨强较大时，雨水的入渗不仅会增大孔隙水压力，且易使张裂缝充水形成静水压力，对边坡稳定不利。结合降雨条件下饱和-非饱和渗流分析，考虑降雨过程中的瞬态孔隙水压力场与瞬态强度场，并同时考虑张裂缝充水时的静水压力，对边坡临界滑动场法进行改进，提出降雨条件下具有张裂缝边坡临界滑动场数值模拟方法，且对其进行了验证。将该方法用于一个典型均质黏土边坡算例，结果表明，（1）文中方法可考虑张裂缝具体位置、深度及其充水状态下对边坡稳定性的影响，并能搜索出任意形状危险滑面，计算结果合理可靠；（2）降雨条件下张裂缝中静水压力对边坡稳定性及滑面形状有较大影响；（3）降雨条件下张裂缝位置对边坡稳定有较大影响，距坡肩越近，张裂缝对边坡稳定性影响越大；（4）张裂缝处在最不利位置且充水时存在一个最不利深度。

Critical slip field of slope with tension crack under intensive rainfall

Pore water pressure and water table in the tension crack will increase gradually under the long duration rainfall with high intensity and it will be adverse to the slope stability. In combination with transient unsaturated seepage calculation, an improved numerical procedure for critical slip field of slope with tension crack under intensive rainfall is proposed. In this procedure, transient pore water pressure field, the location of crack and hydrostatic pressure in crack can be taken into account, put forward under the condition of rainfall has a crack slope critical sliding field numerical simulation method, and its are verified. This procedure has been applied to the stability analysis of a typical clay slope. The results show that: (1) The method can search for any shape of the dangerous slip surfaces under the condition of considering the location of tension crack and hydrostatic pressure in crack; and the safety factor is reliable. (2) Hydrostatic pressure in crack has great influence on slope stability and searching for the sliding surface. (3) Crack location has great influence on slope stability under rainfall; and the closer to the slope shoulder the location of tension crack is, the more unstable the slope is. (4) There is a most disadvantageous depth of tension crack when tension crack is located at the most disadvantageous position.