摘要
强降雨作用通常是触发大型滑坡的主要诱因,为更好地研究降雨条件下滑坡的变形破坏机理,分析计算降雨入渗作用引起的暂态孔隙水压力、岩土容重变化及岩土抗剪强度对滑坡稳定性的影响,将模糊随机可靠性理论引入滑坡的稳定性分析中,探讨滑坡渐进破坏的时空演化特征。通过推导降雨作用下考虑基质吸力的滑带土条块安全余度的表达式,并在此基础上,同时考虑滑带土强度参数及功能函数的模糊随机性,分别计算条块的局部破坏概率、扩展破坏概率和渐进破坏概率,从而研究降雨作用下滑坡时空演化过程。以嵩县白河滑坡为例,计算结果表明:长期持续的强降雨入渗是其诱发的主要因素,其斜坡变形破坏模式属于孔隙水压力诱发的平推式地质模式。最后应用模糊随机可靠性理论分析了滑坡发生→发展→破坏的动态演化过程,结果可为支护设计提供理论依据。
Heavy precipitation is usually the main factor to trigger the large landslide. In order to research the deformation failure mechanism under the precipitation condition, and to analyze the factors such as the transient pore water pressure, change of soil bulk density and geotechnical shear strength, which influence the stability of landslide, the fuzzy random reliability theory was introduced into the stability analysis on the landslide to explore the spacetime evolution gradual damage characteristics of the landslide. First of all, the slice safety allowance expression was deduced under the action of rainfall considering the effect of matrix suction, and then, on the basis of this, the fuzzy randomness of strength parameters sliding soil and the performance function were considered, the local failure probability, the gradual damage probability and the transfer probability were studied respectively, so as to research the spacetime evolution process of landslides essentially under precipitation. Taking the Baihe landslide as an example, a longterm rainfall in filtration is the main reason to its occurrence. The deformation failure mode belongs to flat push geological model induced by pore water pressure, and the fuzzy random fuzzy reliability theory was applied to analyse the dynamic evolution process, from occurrence, development to damage process, in order to provide a the ory basis for the support design of the landslides.
出处
《水利学报》
EI
CSCD
北大核心
2013年第4期416-425,共10页
Journal of Hydraulic Engineering
基金
国家自然科学基金项目(41027001)
国家重点基础研究发展计划(973计划)项目(2009CB724605
2010CB731501)
中国地质调查局工作项目(121201 1014026)
关键词
降雨
渐进破坏
破坏概率
基质吸力
模糊随机理论
precipitation
progressive failure
failure probability
fuzzy stochastic theory
matric suction
