Sensitivity Research Of The Slope Structure Reliability To Random Parameters

In geotechnical engineering, the slope stability is a very important issue. The traditional certain safety factor method is used to evaluate the slope stability by scholar worldwide, but the randomicity of parameters is not considered in this method, so it has some errors compare with reality. Some research results about using reliability method to analyze the slope stability are also reported, but these research are not mature enough at present.In this paper, a multiple method is introduced, which consist of reliability analysis method and random perturbation theory. This subject regards the terrene slope as research object, which is quite common in projects, then the influence of the variability of soil parameters and correlation coefficients to safety factor and reliability index is discussed in this paper. Take the homogeneous slope and multilayered slope for example, traditional safety factor method is adopted to search the critical slip surface at first, then a multiple method is applied, which consist of the slice method of slope stability analysis, reliability method and random perturbation theory. The current calculation formula of the safety factor and reliability index in multilayer slope is given when the randomness of parameters is considered, and the corresponding C++ program is also compiled. The effect of soil parameters random disturbance to reliability index is also analyzed under the situation of independence and correlatedness. The effect of correlation coefficients random disturbance to reliability index is analyzed. Some conclusions are turned out as follows:1. The effect of soil parameters random disturbance to safety factor is same under the situation of independence and correlatedness.2. In monolayer terrene slope structure, the effect of reliability index sensitivity to the cohesion c is same when it has small positive and negative disturbance around its mean value, the effect of reliability index sensitivity to the friction coefficient f and the gravity coefficientγis not same when they have small positive and negative disturbance around their mean values.3. In multilayered terrene slope structure, the reliability index increase with the decrease of correlation coefficients between layers.4. In monolayer terrene slope structure, the reliability index is bigger when soil parameters relativity is considered, in multilayered terrene slope structure, the conclusion is still right when the soil parameters relativity inner layer is just considered.These results have some reference values in the reliability analysis aspect in engineering designing, construction, evaluating of slope structure.