The Shaking Table Test Study Of Dynamic Failure Mechanism Of Bedding Rock Slope

The effect of earthquakes influences a lot on the destruction of the slope,especially for the bedding rock slopes which have special structure.Recent years,the earthquakes occur frequently in China.With the effect of earthquake,the problem of bedding rock slope's dynamic failure is especially prominent.This paper aims to study the dynamic response and dynamic failure mechanism of the bedding rock slope by means of shaking table test method and theoretical analysis.The main work and achievements are as follows:(1)Based on the bedding structure of Wuli slope mudstone and sandstone,and taking five groups of inter-bedding combination and two sets of horizontal inter-bedding combination as concept model,the large-scale shaking table test of the model slope is designed and performed.And established a set of testing design ideas and testing method which is fit for soft and hard bedding rock slope for shaking table test.(2)Based on the dynamic response analysis of the seven group of mudstone-sandstone combinational slope with respect to elevation,lithology,amplitude and spectrum,the results show that inter-bedding combinational slope is characterized as the distinct elevation,lithology,amplitude and spectral effects.And the horizontal inter-bedding combinational slope is characterized as significant elevation,amplitude and spectral effects effect.(3)Through the analysis of the stage,location and spacing of fracture in the whole process of the 7 groups ' failure,the failure modes of inter-bedding and horizontal inter-bed ding is proposed.The results show that the slope has three distinct stages during the process of dynamic failure process:the tension stage,the tensile fracture propagation stage and the tensile and shear fracture through the sliding stage.(4)Through the analysis of the dynamic response and failure process of Wuli slope model,the experimental results are same with the the dynamic response and the earthquake damage of the Wuli slope after Wenchuan earthquake.(5)By introducing the mechanics analysis theory of the fracture spacing of the layered rock mass and the " fracture saturation",the theoretical explanation of the relationship between the reduction of slope fracture and the interlayer shear slip is given.By comparing the fracture data during the process of slope failure,it is in good agreement with theory.