Slope Stability Analysis Using Monte Carlo's Technique Of Constant Angle Of Rotation With Finite Element Method

The problem of slope stability is always an important research subject in the civil engineering, in Geotechnical Engineering. The stability of all kinds of natural slope, highway, airport, refuse dump, dam, fill, excavation need to be analysed.The core of the slope stability analysis includ two contents. First, it calculats the safety factor of the given the sliding surface. Second, in all the possible sliding surface,it continues to repeat the above steps to find the critical (the most dangerous) sliding surface, namely,the minimum safety factor corresponding the sliding surface.Currently, there are many methods to calculate the slope stability. These methods are both advantages and disadvantages in slope stability analysis.New theories and methods have been applied in the slope stability analysis,however, these new methods will be further matured and improved,and will be further tested in actual work.First,This paper calculated the internal stress of slope with the elastic-plastic finite element method.Second,the most disadvantaged sliding surface is searched with Monte Carlo which sliding surface rotating with regular angle. Its advantage not only considers the soil's stress-strain relationship, but also is good to find the global's minimum sliding surface. This paper used FORTRAN90 to design the program, inputting the the original data which the stress Calculated by FEM;Inputting the number of the slope's Inflexions and Coordinates; Inputting the number of the Initial sliding surface's Inflexions.The program would calculate the minimum safety factor and find the most disadvantaged sliding surface's position.In this paper, three examples were calculated, and the results were analyzed. The results show that the result which calculated with this paper's method is less than others' for the same definition of safety factor. What the reasons are these:first, this method makes full use of the capacity of Monte Carlo searching the global's minimum, searching the critical slip surface and the safety factor of the slope effectively, overcoming most optimization methods' problem which going into the local's minimum in searching.secondly, this paper's method calculated the slope's stress with the elastic-plastic finite element method.the Mohr-Coulomb model was used to simulate the nonlinear stress-str tual situation.ain relationship of the slope.Compared with the limit equilibrium method, the stress of the sliding surface calculated with this paper's method is more tally with the actual' stress.