Study on slope stability analysis and large deformation characteristics of failure based on SPH method

Slope instability failure is a large deformation problem. Traditional numerical methods and limit equilibrium methods are difficult to characterize the whole process of failure, resulting in unclear analysis of instability mechanism. A meshless method, smoothed particle hydrodynamics (SPH) method, is used to establish a numerical model of soil deformation and failure by adopting Drucker-Prager yield criteria to characterize the mechanical properties of soil. The validity of the model is verified by shear test, biaxial compression test and soil self-weight test. The damping coefficient and improved stress normalization algorithm are introduced to optimize the slope stress distribution and overcome the short-scale noise problem. Finally, the numerical simulation of the whole process of slope progressive instability failure is realized. On this basis, the tolerance is adopted. Based on the displacement mutation criterion, an improved SPH safety factor algorithm is adopted to calculate the slope safety factor and compared with the results of finite element software. The results show that SPH can effectively characterize the whole process of progressive failure of soil slope instability and overcome the shortcomings of non-convergence in the study of soil material deformation and failure by traditional numerical methods. At the same time, the improved SPH safety factor discrimination method overcomes the shortcomings of the fixed reduction coefficient algorithm and improves the calculation efficiency of the safety factor based on the meshless theory. The research results can provide a new method and idea for studying the disaster range and stability analysis of slope failure.