三峡库区滑带土抗剪强度参数的统计规律研究

Study on statistical rule of shear strength parameters of soil in landslide zone in Three Gorges Reservoir area

收集和整理了近年来三峡库区地质灾害防治工程中近400处滑坡的勘察资料,采用地质分析和工程地质类比法,指出三峡库区内存在5类易滑地层。运用K-S有限比较法,对3 308组抗剪强度参数试验数据分类进行了拟合优度检验,发现5类易滑地层中滑坡滑带土的c、φ值一般均能接受正态和对数正态分布,但c值与φ值相比,最优分布服从对数正态分布者更多,而服从正态分布者更少。针对区内滑带土普遍含有碎石的显著特点,对φ值与碎石含量的相关关系进行了线性回归分析发现滑带土φ值与含石量呈现良好的正相关关系。

Data about 400 landslides in Three-George reservoir area were collected and summarized in recent years. It is concluded that there are five types of sliding-prone strata in reservoir area on the basis of geologic analysis and engineering geology analogy analysis. Through K-S finite contrast method, test of goodness of fit was respectively carried out on 3 308 groups of shear strength parameters; and the results showed that distribution forms of parameters c and φ are normal distribution and logarithmic normal distribution. The optimum fits of probabilistic models of c are mainly logarithmic normal distribution. As there are gravels in soil in landslide zone, linear regression analysis was carried out between the gravel content and the parameter φ of soil in landslide zone and the results indicated a well positive correlation relationship.