中文摘要：

红粘土是广泛分布于西南地区的一种特殊土，其物理力学性质随含水量的变化很大。该文以毕节三个不同地点滑坡带红粘土为研究对象进行了直剪试验。研究了含水量对红粘土的粘聚力、内摩擦角的峰值强度和残余强度影响规律。实验结果表明：随着含水量的增加，红粘土的峰值粘聚力和残余粘聚力均呈一阶负指数衰减，最后具有稳定趋势。峰值内摩擦角和残余内摩擦角均呈线性关系下降。

英文摘要：

Red clay is a kind of special soil,widely distributed in southwest China, and its physical and mechanical properties vary significantly with the change of moisture content. Taking the red clay of three different landslide zones in Bijie, this paper performs a direct shear test to study the impact rule of moisture content on the cohesion of red clay, the peak intensity of internal friction angle and residual strength. The experimental results show that with the increase of moisture content the peak cohesion and residual cohesion of red clay present the first-order negative exponential attenuation and final sta- bilization, and the peak internal friction angle and residual internal friction angle present a linear decline.