Stability Analysis Of Heterogeneous Slope Based On Two-dimensional Random Field Theory

In slope engineering,most engineers use deterministic analysis methods to study the stability of the slope.Although this type of method can quickly obtain the slope safety factor,it does not take into account the structure of the rock and soil.Mechanical properties and external loads are changed in the orthogonal direction,thus ignoring the spatial variability of soil parameters.Therefore,based on the deterministic analysis method,it is necessary to use the two-dimensional random field theory to describe the spatial variability of soil parameters.In this paper,the spatial variability of material parameters is described by the random field theory.The correlation function,the probability distribution form of material parameters,and the influence of distance on the stability analysis of the slope are analyzed in detail.Then,considering the cohesion force as a function of airport and internal friction angle,the sensitivity of material parameters to slope stability analysis is compared.Finally,the slope stability safety factor under random field theory is calculated,and the effect of introducing random field theory on slope stability analysis is illustrated by the mean,standard deviation,relative error and absolute error of safety factor.The main research results are as follows:(1)The triangular,exponential,and exponential cosine correlation functions are close to each other at different correlation distances,and the Gaussian correlation function averages the safety factor at different correlation distances.The values are small.(2)Comparing the calculated standard deviation of the safety factor and its relative error with the result of the limit equilibrium method,it can be seen that the calculation result of the logarithmic normal distribution of soil material parameters is more reliable than the normal distribution.(3)The smaller the vertical correlation distance,the more the number of discrete units in the field,the smaller the calculated safety factor,and the closer to the limit balance method the calculated safety factor;the larger the vertical correlation distance,the number of discrete units in the random field The fewer the calculated safety factor,the greater the deviation from the limit equilibrium method.(4)Compared with the internal friction angle random field,the cohesion force is more sensitive to the results of the airport's slope stability analysis,and neglecting the cohesion force,the safety factor calculated with the airport fluctuations are large.(5)In the case of the same number of discrete units,the slope safety factor calculated by the finite element method is smaller than when introducing random fields.