Integration Method Based On Three-dimensional Numerical Simulation Of Slope Stability Analysis

It is a especially important topic of development for slope stability analysis method investigation in geotechnical engineering. Taking moraine soil slope in west wall of Taihe Iron Mine as a practical engineering background and basing on 3-dimension numerical simulation, a "diamond" system frame supporting each other whose five vertexes are belong to a triplex layer which is composed of fundamental parameters ("strength simulation" unit), assessment indexes ("stress-strain analysis", "safety factor" and "reliability"unit) and comprehensive analysis ("comprehensive analysis" unit) is constructed, and a "integrate method" of slope stability analysis is established in this dissertation. Its conspicuous characteristics is that comprehensive analysis of multi-indexes which integrate 3-dimendion stress-strain analysis with overall reliability and safety factor is accomplished finally in same slope engineering through introducing "strength reduction technique" and "simplified first-order second-moment method (SFOSM method)".Parameters of strength and deformation of moraine soil are not only fundamental inputting data but also are bottlenecks of moraine soil slope stability analysis, and it isn't solved that how to acquire them in geotechnical engineering all the time. A method in which cellular automation is couple with finite difference method is adopted to simulate parameters of strength and deformation of moraine soil in this study. Cellular automation method is adopted to simulate structure of moraine soil and construct large-scale emulational trier. Afterward, triaxial numerical simulation tests are carried on the emulational triers by use of FLAC^3D, while parameters of strength and deformation of moraine soil are obtained on the basis of mechanical formulas of general triaxial test. Taking this as the basis, triaxial simulation tests are carried out repeatedly and many simulation samples of shear strength parameters of moraine soil in Taihe Iron Mine are obtained. After statistical analysis and non-linear fitting, two experiential forecasting models of shear strength such as determinacy model and probability model are suggested respectively. Thus, they would be provided reliable strength parameters for design and evaluation of stope slope engineering in Taihe Iron Mine.Two main work is carried out on the part of slope reliability in this study. First, according to the basal principle of mean first-order second-moment method and classical computational method of safety factor, SFOSM method is presented. In 2-dimensional space, reliability model needn't to be established when we use this method, and potential failure surface of minimal reliability index can be rapidly searched to acquire slope failure probability. Slope failure probability corresponding specified failure surface is also rapidly acquired by use of it. Second, overall reliability(or failure probability) responding to overall safety factor is directly obtained by use of the method in which 3-dimension finite difference method combine with Rosenblueth method. Thus, variational characteristic of safety factor and reliability is cross-over analyzed under the condition of uniform mechanical response characteristic of rock and soil mass in 3-dimensional space.The problems stem from Taihe Iron Mine, while integrate method presented by this study is applied to Taihe Iron Mine. And a integrated stability analysis of moraine soil slope in west wall of Taihe Iron Mine is accomplished in this study. In order to keep the structure integrality of "integrate method" in this dissertation, the analysis results are distributed into relevant chapters.