Study On Shear Strength Of Slip Zone Soil And Slope Stability Analysis

Landslide is one of the major geological disasters nowadays. With the development of human society and the needs of engineering constructions, we pay more and more attention to the problem of slope stability and the resurrection of ancient landslide. In this paper, an ancient landslide nearing the dam area of a major project in Guangdong Province was studied, we investigated the shear property of slip zone soil and analyzed the stability of the ancient slope, such as the experimental researching about the shear property of undisturbed soil through the in-situ direct shear test, made a conclusion about the relationship between the shear stress and strain of slip zone soil, discussed the main influencing factors of the direct shear test on the basis of reading related literature proverbially, investigating the project, and summarizing the current shear test methods and some of outputs.At the same time, with a comparing to different tests results that come from natural soils out door to remolded soils in the laboratory, this thesis analyzed the characteristics and the main impact factors about the shear strength of slip zone soil further.To resolve the problem of the shear box tilt which caused by the extrusion of fine-grained soil containing coarse particles, two improved model of shear box were designed. Furthermore, we demonstrated its reliability through experiments. With the reformed shear box, this thesis approached the mechanisms about the shear strength of natural slip zone soils. With some remolded soils containing different percentage of coarse particles, we made a further study about fine-grained soil containing coarse particles. At last, according to the test results about slip zone soils above, the thesis made a stability analysis about the ancient landslide and raised the recommendations to prevent and control it.