中文摘要：

基于香根草根系分布和根系抗拉力的一系列试验,利用Weibull函数描述了根系抗拉力分布;通过对拟合的函数进行分析,当各种直径的根系数量比例相同的情况下,根数变化对函数参数值并没有显著的影响。通过根土复合体试件的直剪试验,得到了原始的统计方法和按新的根系抗拉力分布函数的Riproot模型计算的结果,结果表明：2种方法得到的数据是基本一致的,且利用Weibull函数得到的粘聚力增加值更加符合试验结果;Weibull函数的统计方式克服了原始方法的缺陷,在计算上也更加简洁。最终的结论为根土复合体抗剪强度研究和植物边坡稳定分析提供了理论基础。

英文摘要：

On a series of tests for distribution and tensile strength of vetiver roots,distribution of root tensile strength is obtained by using the Weibull function; Though analysis of the fitting function,when the proportion of various diameter of root is controlled,the change of root number is not sensitive to the parameter value. Based on the direct shear test of root-soil composite,calculation results are attained by using original and new method. Results showed that： Data from the two methods is consistent,and the calculating data of increased cohesion by using Weilbull function are more close to experimental data; Statistical methods using Weibull function overcomes the defects of original method,and calculation is more simple. Conclusion provides a theoretical foundation for the research of shear strength of root-soil composite and an essential prerequisite for stability analysis of plant slope.