The Improvement Of Multi-point Estimate Method And Application In Slope

Slope stability study has long been a hotspot in the geotechnical engineering field. Structure and composition of the slope rock and mass are uneven and there is a strong spatial and temporal variability, as the value of the safety factor used to evaluate the slope of the standard evaluation of traditional methods can not reflect the uncertainty in slope engineering, and the reliability analysis methods of rock and soil slope stability full account of random parameters, have more practical significance. As the complexity of engineering itself, its stability limited performance function is generally more extreme point, non-convex of the implicit function, so the reliability of using the general method such as first order second moment reliability method exists difficult to calculate derivatives, and response surface methods, stochastic finite element method and so have different limitations.Point estimate method as a simple and efficient method of reliability analysis, has been applied in the building structural engineering, foundation engineering and other field, and achieved good results. Therefore, the paper dedicated to the research for a reliability analysis of reliability method, which based on point estimate method to caculate statistical moments of the function and use Pearson curves to simulate approximate probability density function of slope stability performance function, and Then direct integration in the failure zone to calculate the reliability. Hoping to give some reference value to the researchers.For the above problems, this paper conducted a study of the following:(1) Combined The principle of Gauss-Hermit numerical integration with point estimate method , Take the Bishop model of slope stability limit equilibrium analysis as an example, established a seven-point estimate method of slope reliability analysis.(2) For the limitations and shortcomings of the commonly used slope reliability compute method, introduced the multi-point estimate method and Pearson curve, simulation of the approximate performance function slope stability probability density function, and compared its performance with approximate direct integration method which based on maximum entropy method and Monte Carlo simulation.(3) The physical mechanics parameter of rock and soil along the Henggui highway’s side slope has tested through the indoor experiment, analyzed the the fractal model of red sandstone collapse, and analyzed the rock and soil of side slope’s water content change to cause the intensity change tendency of rock and soil intensity, for the infiltration of rain water caused changes in soil shear strength of the slope stability of embankment slope were analyzed, provide a reference for project.