The Stability Analysis Of Landslides Based On Random Fields

One of the main problems in slope stability analysis is the uncertainty of geotechnical properties,especially its inherent variability,even in a homogeneous soil medium the soil properties exhibit variability by nature.Because of the uncertainty of geotechnical properties,using the reliability theory of slope stability analysis is more reasonable than the fixed value analysis method.Therefore,in this paper,the reliability theory and random field theory is used to analyze the stability of toe circle slope,base circle slope and stepped slope,and the accuracy of slope stability analysis is improved when the slice method is replaced by the integration method.Conclusions:(1)For homogeneous toe circle slopes,the closed-form solutions of the mean of the safety factor and the failure probability of the slope are derived using the horizontal integration method and the vertical integration method.Compared the mean of the safety factor obtained from the horizontal integration method and the vertical integration method with those obtained from the traditional Swedish slice method and the Spencers method respectively,compared the failure probability of the slope obtained from the horizontal integration method and the vertical integration method with those obtained from NIRFS and Ji respectively,it can be see that the vertical integration method is more consistent than the horizontal integration method.Therefore,it is better to choose the vertical integration method to analyse the stability of the homogeneous toe circle slopes than the horizontal integration method.(2)For homogeneous base circle slopes,the closed-form solutions of the mean of the safety factor and the failure probability of the slope are derived using the horizontal integration method and the vertical integration method.Compared the mean of the safety factor obtained from the horizontal integration method and the vertical integration method with that obtained from the traditional Swedish slice method respectively,it can be see that the mean of the safety factor of the slope obtained from the vertical integration method is in good agreement with that obtained from traditional Swedish slice method.Therefore,it is better to choose vertical integration method to analyse the stability of the homogeneous base circle slopes than the horizontal integration method.(3)For layered toe circle slopes,the closed-form solutions of the mean of the safety factor and the failure probability of the slope are derived using the horizontal integration method.The failure probability of the slope obtained from the horizontal integration method is in good agreement with that obtained from the Monte Carlo simulation(MCS).That is to say,the horizontal integration method is a convenient,accurate and feasible method for analyzing the stability of the layered toe circle slopes.(4)For layered based circle slopes,the closed-form solutions of the mean of the safety factor and the failure probability of the slope are derived using the horizontal integration method.The failure probability of the slope obtained from the horizontal integration method is in good agreement with those obtained from Ye and the MCS.Therefore,the horizontal integration method is a convenient,accurate and effective method for analyzing the stability of the layered base circle slopes.(5)For homogeneous stepped slopes,the closed-form solutions of the mean of the safety factor and the failure probability of the slope are derived using the horizontal integration method and the vertical integration method.Compared the mean of the safety factor obtained from the horizontal integration method and the vertical integration method with that obtained from Sun Dongliang respectively,it can be see that the mean of the safety factor of the slope obtained from the vertical integration method is in good agreement with that obtained from Sun Dongliang.Therefore,the failure probability obtained by the vertical integration method is similar to that of Monte Carlo simulation.Therefore,it is better to choose vertical integration method to analyse the stability of the homogeneous stepped slopes than the horizontal integration method.The innovations of this paper are as follows: the random field theory and reliability theory are proposed;the analytical solution of the stability factor and failure probability of slope are obtained;the slice method is replaced by the integral method.