摘要
The orientation of the Madaling landslide is a typical slightly inclined slope with a nearly North-South trend and a soft and hard mutual layer structure.The primarily rock of the slope is sandstone,carbon shale and coal.Inside the slope,there exist a large number of soft rock sandwich and cracks.Two workable coal seams lay in 120m from the top of the slope,and a lot of mined-out area appeared under the slope after the mining of the coal seams.The deformation and stability of the slope is mainly controlled by the strength characteristics of sandstone in roof and the coal seams located in the slope toe.This paper examined the main behaviors of deformation and strength of sandstone and the shear strength characteristics of coal based on the laboratory experiments of rock mechanics,and analyzed the deformation characteristics of the two representative rocks.The results from the tests and the comprehensive analyses indicate that the tensile strength of the sandstone has a controlling role in the stability of the slope and the tensile strength of the coal has the most direct influence on the slope stability.Controlled by the bedding plane,the tensile strength of the coal is very low,and the residual strength is reduced by 60% compared with the peak strength.Significant difference exists in the deformation characteristics of the two rocks because of the different weathering degree.