Research On The Method Of Stochastic Response Surface Reliability Analysis Of Slope Stability

The stability of slope engineering has always been a research focus in geotechnical engineering.However,the large number of factors influence slope stability and these factors have great uncertainty.the use of traditional stability analysis methods(safety factor)has been inaccurate to describe slope stability.So,in this paper,we introduce the reliability analysis method into slope stability analysis.It describes the slope stability by calculating the probability of failure of the slope.This analysis method is more practical for slope stability analysis and evaluation.The commonly used reliability analysis methods include the center point method,the verification point method and the Monte Carlo simulation method.However,the calculation accuracy of center point method is low,besides,the calculation efficiency.of calculation point method and the Monte Carlo simulation method is not high.Therefore,in this paper,the stochastic response surface method with strong mapping ability is applied to the reliability analysis of the slope.In the use of stochastic response surface method,the influence of the collocation point and order on the calculation accuracy in the stochastic response surface method is discussed.the engineering example with the explicit function,the accuracy of the stochastic response surface method is preliminarily verified.Then,it is applied to the reliability calculation of homogeneous slope.Firstly,the sensitivity of the physical parameters affecting stability of the slope is analyzed,and the variable with higher sensitivity is determined.Finally,in the reliability analysis of the Xiawanzi landslide,calculate and analyze the stability of the slope in both natural condition and rainfall state by strength reduction method through the FLAC software.Afterwards,the stability analysis of the slope was carried out by using the stochastic response surface method and Monte Carlo simulation method.It shows that the stochastic response surface method can still accomplish the reliability analysis with high accuracy on the complex slope efficiently.Through simple numerical examples and specific engineering problems,it can be found that the stochastic response surface method has a strong mapping ability to the function response.In addition,in the slope reliability analysis,the calculation accuracy by the stochastic response surface method can be guaranteed,and the computational efficiency is also greatly improved compared to the Monte Carlo simulation method.This shows that it is feasible to apply the stochastic response surface method to slope reliability analysis and it is more superior in reliability analysis in slope engineering.