Experimental Study On The Performance Of Coal Gangue Subgrade And Stability Analysis On Its Embankment

Coal gangue is a kind of solid wastes which produce in the process of coal mine construction, mining and processing, a colored rock accompanying coal seam in the process of coal forming. And it currently has the largest storage quantity of all the solid waste in China.Coal gangue’s great accumulation in the mining area not only can cause the pollution of atmosphere, soil and other environmental problems, also can seriously affect and harm people’s lives and health. Accordingly the treatment and comprehensive utilization of coal gangue has become the urgent issue.In this paper, relying on An-Shao highway coal gangue embankment filling project and the analysis about the mineral and chemical composition of gangue in loudi area and its physical and mechanical properties of different quantity of mixed soil, the feasibility about coal gangue acting as a highway embankment filling is explored,combining with the coal gangue subject "Application and Study on Highway Coal Gangue Subgrade Filling Project "(2010-353-343-290).The main research contents and research results are as follows:l)Test and study the coal gangue engineering characteristics of different amount of mixed soil, conclude the changing relationship between coal gangue basic physical parameters and the quantity of mixing soil content, and analyze the feasibility of coal gangue used as embankment filling and a method to improve road performance.2) An interface friction test of different amount of mixing soil in reinforced gangue is carried out. With the increasement of shear displacement, shear stress increases rapidly, when the shear displacement reaches a certain value, the curve flattens out, peak shear strength and residual shear strength arise.3)By using the hyperbola and exponential model to fit coal gangue shear stress and shear displacement curve, the test results show that neither of the two models reflects shear strain softening phenomenon in the process of coal gangue shears.This paper proposes a model that can reflect shear stress and strain softening in the process of the coal gangue shears, and validate the model’s applicability in fitting coal gangue interface friction test.4) The Interface friction coefficient of Gabion mesh reinforced coal gangue uses residual interface friction coefficient seems more appropriate and the coefficient is generally obtained from experiment, which can be calculated by the formula F=0.8-tanΨc when test data is inaccessible.5) State the design method of coal gangue reinforced slope, and put forward the check formula of reinforced slope stability;analyze the secondary and tertiary platform width of slope and the influence of slope Angle to rupture surface forms, and conclude secondary and tertiary design method of slope to different platform widths.