Research On Horizontal Stratified Soil Slope Stability Based On Limit Equilibrium Theory

Researches of traditional soil slope stability are fruitful, However, the horizontal stratified soil slope failure mode and bearing characteristics have its special characteristics. Therefore, the study has practical value on horizontal stratified soil slope. On the basis of the failure mechanism and bearing characteristics of horizontal stratified soil slope determined by using indoor model tests and numerical simulation analysis, use limit equilibrium method to study the calculation method of the stability of horizontal stratified soil slope’s. Conclusions are as follows:Firstly, using indoor model tests to simulate horizontal stratified soil slope’s vertical settlement, horizontal displacement, ultimate capacity and failure mechanism, and the results showed that the sliding surface of the horizontal stratified soil slope is arc-straight plane,maximum vertical settlement appears at the top of the hill where the loading plate is, maximum horizontal displacement appears at the weak interlayer of the slope; comparing different conditions discovers that ultimate load of the horizontal stratified soil slope increases as the thickness of layer increases, and that the influence that slope height caused to the ultimate load is not obvious.Secondly, applying numerical stimulation to analyze five indoor model tests, the results are close to indoor model test’s results; Through numerical simulation some conclusions are obtained:(1)The changes of horizontal stratified soil slope sliding surface location at different loading crest widths, different thickness, different slope ratio;(2)Relationship between sliding surface location of horizontal stratified soil slope and loading width;(3)Ultimate load increases as thickness and slope ratio increases; When the load scope increases, the ultimate bearing capacity decreases.Thirdly, using the limit equilibrium theory, aiming at failure mode of arc-straight sliding surface, formulas of horizontal stratified soil slope’s limit equilibrium in the method of vertical slice are derived, which is able to calculate the ultimate bearing capacity and safety factor; the formula meets static equilibrium and moment equilibrium, and the calculated results are close to the indoor model test results, which proves its accuracy.Fourthly, considering the level of the hierarchical nature of horizontal stratified soil slope, based on the limit equilibrium theory, applying the horizontal slice method to calculate the stability of the slope,formulas of limit equilibrium of horizontal slice method used to calculate the safety factor and ultimate bearing capacity are derived. The results obtained by the formula are higher than indoor model test results, the average difference is less than the difference between the vertical slice method and indoor model test’s results.Fifthly, based on sliding surface of the numerical stimulation, formula of horizontal stratified soil slope three-dimensional limit equilibrium stability factor are derived, and the calculation results with the numerical stimulation results are close, three-dimensional limit equilibrium method has certain reference value.