非饱和水力参数在计算滑坡降雨入渗过程与稳定性时是至关重要的材料参数。在三峡库区黄土坡滑坡上进行双环渗透试验,获取黄土坡滑坡表土层的饱和渗透系数。对黄土坡滑坡表土层的含水率和基质吸力进行实时监测,采集了黄土坡滑坡表土层中含水率和基质吸力随时间的变化数据,采用van Genuchten土-水特征曲线模型拟合了4个实时监测剖面的土-水特征曲线及其拟合参数。将饱和渗透系数与土-水特征曲线拟合参数代入van Genuchten渗透系数函数模型,求出了黄土坡滑坡表土层在非饱和条件下的渗透系数函数,为黄土坡滑坡在降雨作用下的稳定性计算提供了可靠的水力参数。
Unsaturated hydraulic parameters are very important for calculating rainfall infiltration process and stability of landslides. Double rings infiltration tests are conducted on Huangtupo landslide in Three Gorges reservoir area to obtain the saturated hydraulic conductivities of the shallow soil deposits of the landslide. The water content and matric suction of the shallow soil deposits of the landslide are monitored using real-time monitoring system; and a large amount of data is gotten. The soil-water characteristic curves and their fitting parameters are simulated with the van Genuchten's three-parameter model for the soil-water characteristic curve. Substituting the saturated hydraulic conductivities and the fitting parameters into van Genuchten's hydraulic conductivity model yields the hydraulic conductivity function of the shallow soil deposits of Huangtupo landslide under tmsaturated condition. Therefore, the hydraulic parameters for calculating stability of Huangtupo landslide under rainfall effect are obtained.