中文摘要：

堆积碎石土是不同于土和岩体的一种不连续非均匀介质,以其作为坡体物质的滑坡广泛分布于中国西南及西北地区。考虑连续强降雨雨后滑坡的失稳机理,分析不同含石量、含水率和周围压力状态下堆积碎石土的主应力差-应变曲线、孔压-应变曲线、破坏形态以及相应的抗剪强度指标的变化规律。研究结果表明：由于碎石的存在,堆积碎石土的主应力差-应变曲线大多呈＂台阶状＂分布并具有应变硬化现象;含石量和含水率是影响堆积碎石土剪切特性的关键因素,当含水率不变,随含石量增大,黏聚力减小,内摩擦角增大;当含石量不变,随含水率增大,黏聚力先增大后减小,内摩擦角减小;存在某一最佳含石量和最优含水率组合下的堆积碎石土抗剪强度最大,该组合指标特征可作为判断连续强降雨雨后堆积碎石土滑坡失稳临界状态的理论支撑依据之一。

英文摘要：

Eluvial gravel soil is a kind of noncontinuous and inhomogeneous material,which is different from soil and rock mass.Besides,as slope or landslide material of landslide,it is widely distributed in southwest and northwest of China.Based on instability mechanism of landslide failure after continuous heavy rainfall,this paper analyzes the changing rules of curves of principal stress difference-strain,curves of pore water pressure-strain,failure mode,and shear strength parameters of eluvial gravel soil with different stone contents,moisture contents and confining pressures.The research results show that,most of curves of principal stress differencestrain demonstrate the ladder-like distribution and eluvial gravel soil has a strain hardening phenomenon.Stone content and moisture content are the critical factors for shear properties of eluvial gravel soil.When the moisture content remains the same,with the increase of stone content,cohesion decreases and internal friction angle increases;when the stone content remains the same,with the increase of moisture content,cohesion first increases and then decreases,and internal friction angle decreases.And shear strength of eluvial gravel soil is the largest under thecombination of the best stone content and the optimum moisture content,the characteristics of composite index can be used as a theory judgment for landslide failure after continuous heavy rainfall.