针对西南地区某大型水电站近坝段内一土石混合体构成的滑坡，利用改进的双环注水试验设备进行了现场渗透试验。试验中在滑体和滑带的不同部位分别布置了4个试验点和6个试验点。试验结果表明：土石混合体的渗透系数较大，接近无黏性粗粒土的渗透系数，并且滑体处平均渗透系数是滑带处的3～4倍。结合室内颗粒分析试验对滑体和滑带土进行的分析表明，低于5 mm粒径的细颗粒含量、密度、颗粒形状及物质来源等因素导致两者渗透系数差异的主要原因。

For a landslide made up of soil-rock mixture near the dam of a large hydropower station in southwest China, in-situ infiltration tests were carried out by using improved double-ring infiltrometer. Four points at different places in the sliding body and six points in the sliding zone were tested respectively. The research indicated that the infiltration rate of soil-rock mixture was quite large and was close to that of non-cohesive coarse-grained soil. Meanwhile, the average infiltration rate in sliding body was 3-4 times larger than that in the slide zone. Indoor granulometric test on the soil of sliding body and sliding zone indicated that the content, density, particle shape and source of soil with diameter less than 5 mm are the main causes of infiltration rate difference.