Analysis For Slope Structure From Water Content To Its Structural Safety Index And Slope Structure Numerical Simulation

The slope stability is a very important issue in geotechnical engineering. Water content is important effect factor to slope stability. It is very necessary to research the effect from water content to slope structure safety index (reliability indexβand factor safety K).In this paper, finite element method analysis, reliability analysis method and perturbation theory are applied, this subject regards the soil slope as research object, which is quite common in projects, then the influence of theωto K andβis discussed. The main conclusions are as follows:1. The effect fromωdisturbance to soil parameters and slope structure is visible, and the moreω, the more really displacement and stress and strain of slope structure.2. The current calculation method of the K of slope structure by using FEM analysis is applied. The relation betweenωand K of slope is very close based on analysis conclusion, and the moreω, the less K of slope structure. K0 is 1.25, which is allowable safety factor in criterion.ω0 is critical water content to assure slope stability under K0 is 1.25. Whenωis smaller thanω0, that is to say that K is bigger than K0, the slope structure is stability, and the relation betweenωand K of slope is close to linear. Whenωis bigger thanω0, and K is smaller than K0, and the slope structure is failure, and the relation betweenωand K of slope is close to linear, and its slope increases.3. Part Second-Order Second-Moment (PSOSM), which is a structural reliability calculation method, is given out in this article. Moreover, the detail formula of structuralβaccording to the PSOSM method is also turned out, and the corresponding VC++ program is also compiled. The calculation results show: the reliability indexβrapidly increases with the light decreasing ofω, and the relation betweenωandβof slope is nonlinear, but the nonlinear degree is slight, vice versa.4. Reliability indexβof slope is figured out by using FEM and PSOSM, and the calculational results is consistent under the differentω. The calculation results show: the PSOSM calculation quantity is less, and calculation efficiency is much higher, and its convergence rapidity is much faster, and its calculation time is much shorter, so the PSOSM can be spreaded to be used in the non-linearity limit state equation of structure.These results have some reference values to the reliability calculation and analysis in engineering design, construction, evaluation of slope structure safety and reliability.