顺层岩质边坡稳定分析中的水力作用研究

地下水作用导致岩质边坡稳定性降低的过程是复杂的。将边坡地下水分为出流处被堵塞和顺利出流两种情况,并针对传统岩层结构面静水压力分布假设的不足,提出了新的静水压力分布假设。基于水压分布假设,得到了岩质边坡静水压力与结构面的长度、岩层倾角及后缘张裂隙充水深度有关。以顺层岩质边坡为例进行分析计算,表明边坡地下水出流处被堵塞情况对边坡稳定最不利,施工中应当加强截排水工作;新假定计算结果与实际情况较吻合,比传统静水压力分布假设更为合理,稳定性计算结果更为保守;动水压力对边坡稳定性的降低作用可忽略不计;边坡后缘张裂隙的充水深度与边坡结构面上的静水压力大小呈正相关,充水深度越大,地下水对边坡的稳定性影响就越突出。

Study on hydraulic effect in stability analysis of consequent bedding rock slope

The stability deterioration of rock slope due to groundwater is complicated. We classify the groundwater flow in slope fissure into two cases of plugged drainage point and free outflow, and suggest new hypothesis of hydro-static pressure distribution according to some defects in previous studies. Based on the new hypothesis, the hydro-static pressure in rock slope fissure is related to the length of the structural plane, the inclination of the rock bedding and the water filling depth in the rear tension crack. The calculation shows that the case of drainage point plugged is the most unfavorable situation for the slope stability, so the drainage work should be strengthened in construction; the new hypothesis is relative accordance with the actual conditions, and its hydro-static pressure distribution is more reasonable than previous distribution, giving a more conservative stability result; the impact of hydrodynamic pressure on slope stability could be negligible; the water filling depth in the rear tension crack of the slope is positively correlated with the hydro-static pressure on the slope structural plane, namely the deeper the groundwater depth is, the more notable the impact on slope stability is.