3震源区的应力状态3.1压力轴、张力轴和零轴以上分析表明,破裂面的取向与引起破裂的应力状态有关.在岩石层内,岩石处于高围压状态.如果以p1,p2,p3轴分别表示震源区在破裂前的主(张)应力轴,那么破裂面(即断层面)与最小主(张)应力轴(最大...3震源区的应力状态3.1压力轴、张力轴和零轴以上分析表明,破裂面的取向与引起破裂的应力状态有关.在岩石层内,岩石处于高围压状态.如果以p1,p2,p3轴分别表示震源区在破裂前的主(张)应力轴,那么破裂面(即断层面)与最小主(张)应力轴(最大主压应力轴,也就是p3轴)的夹角θ(图19)随内摩擦系数μi的增大而减小(Kirby,1980).地震时,沿断层面释放了一定大小(例如大小为p)的剪切应力,这相当于在与断层面成45°和135°角的方向上释放了数值上等于p的压应力(以P表示)和数值上也等于p的张应力(以T表示)(Stauder,1962;Stein and Wysession,2003).展开更多
In order to determine the slip plane of slope directly by the calculation results of strength reduction method, and analyze the influential factors of slope stability, a numerical model was established in plane strain...In order to determine the slip plane of slope directly by the calculation results of strength reduction method, and analyze the influential factors of slope stability, a numerical model was established in plane strain mode by FLAC3D for homogeneous soil slope, whose parameters were reduced until the slope reached the critical state. Then FISH program was used to get the location data of slip plane from displacement contour lines. Furthermore, the method to determine multiple slip planes was also proposed by setting different heights of elastic areas. The influential factors for the stability were analyzed, including cohesion, internal friction angle, and tensile strength. The calculation results show that with the increase of cohesion, failure mode of slope changes from shallow slipping to the deep slipping, while inclination of slip plane becomes slower and slipping volume becomes larger; with the increase of friction angle, failure mode of slope changes from deep slipping to shallow slipping, while slip plane becomes steeper and upper border of slip plane comes closer to the vertex of slope; the safety factor increases little and slip plane goes far away from vertex of slope with the increase of tensile strength.展开更多
文摘3震源区的应力状态3.1压力轴、张力轴和零轴以上分析表明,破裂面的取向与引起破裂的应力状态有关.在岩石层内,岩石处于高围压状态.如果以p1,p2,p3轴分别表示震源区在破裂前的主(张)应力轴,那么破裂面(即断层面)与最小主(张)应力轴(最大主压应力轴,也就是p3轴)的夹角θ(图19)随内摩擦系数μi的增大而减小(Kirby,1980).地震时,沿断层面释放了一定大小(例如大小为p)的剪切应力,这相当于在与断层面成45°和135°角的方向上释放了数值上等于p的压应力(以P表示)和数值上也等于p的张应力(以T表示)(Stauder,1962;Stein and Wysession,2003).
基金Project(20060533071) supported by the Doctoral Program Foundation of Higher Education of ChinaProject (20060400264) supported by China Postdoctoral Science Foundation+1 种基金Project (50774093) supported by the National Natural Science Foundation of ChinaProject (1343-74236000014) supported by Graduate Student Innovation Foundation of Hunan Province, China
文摘In order to determine the slip plane of slope directly by the calculation results of strength reduction method, and analyze the influential factors of slope stability, a numerical model was established in plane strain mode by FLAC3D for homogeneous soil slope, whose parameters were reduced until the slope reached the critical state. Then FISH program was used to get the location data of slip plane from displacement contour lines. Furthermore, the method to determine multiple slip planes was also proposed by setting different heights of elastic areas. The influential factors for the stability were analyzed, including cohesion, internal friction angle, and tensile strength. The calculation results show that with the increase of cohesion, failure mode of slope changes from shallow slipping to the deep slipping, while inclination of slip plane becomes slower and slipping volume becomes larger; with the increase of friction angle, failure mode of slope changes from deep slipping to shallow slipping, while slip plane becomes steeper and upper border of slip plane comes closer to the vertex of slope; the safety factor increases little and slip plane goes far away from vertex of slope with the increase of tensile strength.
