通过排水剪切试验，揭示出易于产生粒子破碎的土体易于产生体积变化，土体初始结构和粒子破碎难易度对体积变化各阶段的影响。在与之相对应的不排水试验中，产生粒子破碎的土体最终产生了较高的超孔隙水压力，而且孔隙水压力产生的各阶段与排水试验中的体积变化阶段具有良好的对应关系。揭示了不同诱因产生的高速滑坡的共同特征，即在长距离运动中，由于粒子破碎的影响，滑动面土体在不排水条件下，抗剪强度因超孔隙水压力上升而下降，最终导致高速滑坡。同时，由于粒子破碎将导致土体自身渗透系数降低，土粒子破碎因而具有促进超孔隙水压力产生和减缓超孔隙水压力消散的双重效果。%The cons olidated-drained ring-shear test method was used toinvestigate the grain crushi ng susceptibility of samples, while the consolidated-undrained ring shear test w as used to investigate the excess pore pressure generation properties. Under the undrained test, excess pore pressure was generated faster and reached higher va lue at steady state on the sample that has higher grain crushing susceptibility. The test results of sample height change in the drained tests are well related to the excess pore pressure ratio in the undrained tests. From the example studi es a universal property of high-speed landslides with long distance movement was found, of which the shear resistance decrease along with the increase of pore p ressure due to the effect of soil grain crushing. During shearing, a new structu re of soil formed due to the decrease of the permeability coefficient. With this structure, excess pore pressure is generated and accumulated easily, while diff icult to dissipate.
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