滑坡充气截排水有效性数值模拟

为验证充气截排水在实际滑坡中能有效控制坡体地下水位和坡体稳定性，本文以小旦滑坡为例，在滑坡变形破坏发展特征分析和形成机制研究的基础上，采用数值模拟方法研究了充气截排水技术应用在此类滑坡治理中应用的有效性。通过二维有限元数值模拟，分析了不同充气压力下坡体稳定性的变化规律。结果表明：在滑坡后缘适当位置进行充气能够形成稳定的非饱和截水帷幕，达到降低潜在滑坡区地下水位的目的；小旦滑坡的最佳充气压力值为125 kPa，在最佳充气压力作用下，小旦滑坡坡脚未开挖状态下稳定性系数由1.144增大到1.209，开挖状态下的稳定性系数由1.106增大到1.139；雨季边坡后缘入渗量增大的情况下，充气截排水对滑坡稳定性的提高作用更为显著。

Numerical Simulation of the Efficiency of Intercepting Water with Compressed Air in the Treatment of Landslide

In order to verify that the groundwater level and slope stability can be effectively controlled in an actual landslide by intercepting water with compressed air, based on the analysis of the characteristics and the formation mechanism of landslide deformation and failure, taking the Xiaodan landslide as an example, the authors studied the effectiveness of the intercepting water with compressed air applied in the treatment of this kind of landslide. Through a two-dimensional finite element numerical simulation, the variation law of a slope stability under different inflation pressures was analyzed. It is found that by inflating air into the appropriate edge of a landslide, a stable unsaturated water cut curtain can be formed to reduce the groundwater level in the potential slide area. When the inflation pressure is 125 kPa, which is the optimum inflation pressure of Xiaodan landslide, the stability coefficient increases from 1.144 to 1.209 under unexploited condition; while the stability coefficient increases from 1.106 to 1.139 under excavated condition. When the infiltration from the trailing edge increases during the rainy season, the effectiveness of intercepting water with compressed air is more significant for landslide stability.