Stability Analysis Of Rock And Soil Slopes Using Finite Element Method

The stability analysis methods using FEM, which based on strenght reduction, has been made a lot of applying and researching in its fields. How to judge the calculated slope's states, stability or instability, is a key problem for shear strength reduction methods.Firstly, this paper introduced the solution methods of nonlinear static equations and its basic theory, the solve steps and characteristics. Except for those, three convergence criteria were introduced.There are three major criterions for evaluating of failure state. The instability state is judged by the convergence of equation's solution in the first criterion. The curve which expresses the relationship of node largest displacement with reduction coefficient is the judgment of the second criterion. The connectivity of plastic flag is the judgment of the three criterions. Three different case were calculated using the general FEM software------ADINA. Based on the results of FEM, this paper analyzed the stability of calculatedslope separately by three failure evaluation criterions. Besides, the influence factors for accuracy of results were analyzed. The density of grid and tolerance of convergence criteria have relatively big influence for the accuracy of calculated results.Finally, this paper made use of FEM to analyze the stress state and transformation state of a slope in practice. Then combining three failure evaluation criterions to analyze the slope's stability, the analysis result is that the slope is instability. So there need to take some engineering measures to reinforce the slope.