Experimental Study On Soil-water Characteristics Of Unsaturated Tailings And Slope Stability Analysis

There are a large number of tailings slopes in the mining area,which will cause major economic losses and casualties once they are unstable.Usually,the tailing sand in the upper part of these slopes is not saturated,but the tailing sand in the lower part is saturated.However,in the project,the theory of saturated soil is often used to analyze and evaluate the stability of the tailings of the tailings,which is inconsistent with the actual situation.In this paper,the tailing sand of a mine in Ganzhou,Jiangxi Province is taken as the test object.The soil-water characteristic test of non-saturated tailings sand and the related research on slope stability are carried out.The specific contents and results are as follows:(1)Determine the basic physical parameters of the tailings and carry out a soil-water characteristic curve test of the unsaturated tailings sand.Analyze the influence of different factors(dry density,particle size)on the sand-sand characteristics curve of the tailings;use the FX model and The VG model was fitted to the test data and the soil-water characteristic curve equation of the unsaturated tailings sand was obtained.(2)Based on the soil-water characteristic curve equation obtained above,the shear strength calculation formula of unsaturated tailings sand was established;the shear strength of the tailings sands with different moisture contents was obtained,and the shear strength was calculated with the formula.Intensity comparison,the results are more consistent.(3)Considering the matric suction of the tailings sand above the saturation line,the shear strength formula of the unsaturated tailings sand is used to calculate its strength.A method for the analysis of the minimum potential energy of the unsaturated tailings slope is proposed,and the soaking line and matrix are analyzed.Influence of suction and dry density on the stability of tailings slope.(4)Calculate the strength of a tailings slope by using the formula of shear strength of unsaturated tailings.Analyze the stability by using ABAQUS software and obtain the safety factor of tailings slope with different moisture content.The combination of moisture content and safety factor is obtained.By comparing the analysis results of the minimum potential energy method and ABAQUS,the critical slip surface and safety factor obtained by the two are basically the same.