Mechanism and stability analyses of progressive failure of thrust-type landslides
LU Yingfa1,HUANG Xuebin2,LIU Defu1
(1. School of Civil Engineering,Hubei University of Technology,Wuhan,Hubei 430068,China;
2. Headquarter of Geological Hazard Prevention and Mitigation in the Three Gorges Reservoir,Yichang,Hubei 443200,China)
Abstract:A new method of stability analyses of thrust-type landslides was established based on the current methods of landslide stability analysis. A critical state between the failure and stable states was suggested based on the mechanism of thrust-type landslides and its determination was also proposed. Two failure modes were proposed for the progressive movement landslide. For the mode I,the whole slope failure occurred along the soft-weak layer. For the mode II,the landslide failure occurred in the rear edges along the soft-weak layer,and the shear failure happened at the front edge along the sliding body. The critical state moved from the rear zone to the front zone of the landslide progressively,i.e.,new critical state and failure zone are obtained for a progressive failure landslide during the deformation. The“S”shape curve of time and deformation is shown for the different points on the sliding face during deformation period. The relationship of deformation at different points on the sliding face and the height of landslide presents parabolic curve characteristics. Three kinds of curves between time and deformation were proposed based on the mechanical behavior classification of rock-soil mass. Types a and b are the unstable and stable curves between time and deformation of type I respectively,type c is the stable curve between time and deformation of type III. The stable analysis method for computing comprehensive sliding- resistance,main thrust force and displacement based on deformation was suggested. The cause of divergence of FEM was analyzed. A new method to take the sliding face as a boundary condition of FEM was proposed for landslide stability analyses. The condition of sliding face boundary method was described not only with the perfect elasto-plastic model(PEPM),but also with the new constitutive model(JCM).
刘广润. 论滑坡分类[J]. 工程地质学报,2002,10(4):339–340.(LIU Guangrun. Discussion on classification of landslides[J]. Journal of Engineering Geology,2002,10(4):339–340.(in Chinese))
[2]
殷坤龙. 降雨对滑坡的作用机制及动态模拟研究[J]. 地质科技情报,2002,21(1):75–78.(YIN Kunlong. Mechanism and dynamic simulation of landslide by precipitation[J]. Geological Science and Technology Information,2002,21(1):75–78.(in Chinese))
Your browse does not support frame!