Slope reliability analysis based on curvilinear local averaging of a 2-D random field

Abstract In slope reliability analysis, “local averaging” of the statistical soil parameters on the slope slip surface is the main factor influencing the results of the analysis. In this study, we analyzed the curvilinear local averaging of a 2-D random field by equation derivation based on random field theory and statistical analysis. By assuming a circular slip surface, the variance reduction due to curvilinear local averaging was obtained as a function of geometric characteristics of the slip surface and variance at a “point” level, and a simple reliability analysis method for homogeneous natural slope was proposed. The proposed method contains three major steps: statistical analysis of soil parameters by site tests, determination of the limit state curve using a series of deterministic finite element analyses, and the calculation of slope failure probability by integrating the probability density function corresponding to the limit state curve. A comparative analysis shows that the proposed slope reliability analysis method based on a curvilinear local averaging of a 2-D random field is reliable and efficient.