The Study On Stability Judgment Of Gently Inclined Bedding Mudstone Slope In Chongqing Area

During the city construction in Chongqing area, a lot of gently inclined bedding mudstone slope come into being. its strength is low and it is easy to be weathering. It often bring out engineering design mistakes because of its stability evaluation index value is inaccuracy, and the occurrence of slope deformation and engineering examples of investment increase are also common, and create a lot of losses. In Chongqing area, due to the low intensity, weathering, creep characteristics, the investigation people often fail to control the evaluation index accurately during the investigation process of gently inclined bedding mudstone slope, they get the parameters according to the limited indoor test and combine with the engineering experience value instead. The stability evaluation index of slope directly affect the result of discrimination, and the stability state is absolutely sensitive to the calculation index(structural plane index of c、?), the result of the stability evaluation have deviation with the actual situation, so it cause part of control engineering design with so much safety reserve and increase the investment.This article aiming at typical gently inclined bedding mudstone slope in Chongqing area, including investigation, design parameters collection and comprehensive investigation. Through the analysis of anti shear index in investigation, design period, we discuss on the index coincidence degree to the actual condition of destoryed gently inclined bedding mudstone slope and irration in parameters reduction, and we also did researches on the different destroyed mode of gently inclined bedding mudstone slope. Secondly, we analysis the destruction mechanism of different mode through the research on its mechanical properties of mudstone, applying weight analysis and other mathematical analysis method on the stability discrimination, then contrast with the discriminant results that using standardized methods, optimization the index of shear strength reduction method of gently inclined bedding mudstone slope. Finally, researching evolution model and stress strain region of slope stress field with the finite element analysis software for different kind of slope to the gently inclined bedding mudstone slope.The main results are as follows:(1)Mechanical properties of mudstone in Chongqing area: Studied the intensity decay, large deformation, weathering aging and creep characteristics of mudstone under rain, weathering and other geological process.(2)The reduction coefficient of shear strength about the gently inclined bedding mudstone slop in Chongqing area: Based on collected projects data and field research, and combined with the mechanical properties of mudstone understanding after research, we established the mechanics attenuation contact of gently inclined bedding mudstone slope, and put forward more accurate shear strength reduction factor in accordance with this contact.(3)Classification structure surface shear strength index of gently inclined bedding mudstone slope stability evaluation value in Chongqing area: Classification, phased research on different failure modes of gently inclined bedding mudstone slope in Chongqing area, and get the shear index various stages of each failure mode finally, and to determine its stability status, forming a chart.(4)Classification atlas of different slope along gently inclined bedding mudstone slope stress field evolution model, strain region.