On the Location of Multiple Failure Slip Surfaces in Slope Stability Problems Using the Meshless SPH Algorithm

Liang Li,Yungming Cheng,Bin Hu,Ming Zhai,Xuesong Chu,Xianzhang Ling

doi:10.1155/2020/6821548

Abstract

The occurrence of multiple critical slip surfaces with equal importance in rehabilitating and reinforcing slopes has been frequently observed in geotechnical engineering practices. The simultaneous determination of these potential slip surfaces is, however, not trivial. This paper presents a methodology based on the smoothed particle hydrodynamics (SPH) approach, which can simultaneously determine multiple failure slip surfaces and the debris flow process without previous knowledge or trial-and-error processes, and this methodology is validated against a slope with the presence of multiple critical slip surfaces. The proposed methodology serves as an efficient and effective alternative approach to traditional approaches, which involve cumbersome treatments performed by engineers based on their subjective experiences. The multiple sources of failure slip surfaces in slope stability are equivalent to multiple sources of initiation of slope failure, and it is found that SPH can provide a direct and systematic tool for identifying multiple failure slip surfaces. However, some minor potential problems are also found with the use of the SPH method in actual applications.

Highlights

Smoothed particle hydrodynamics belongs to the category of meshless methods originally proposed by Lucy [26] and Gingold and Monaghan [27] for astrophysics problems. e strain and strain rates are large in smoothed particle hydrodynamics (SPH), and the use of frame-invariant Eulerian Jaumann stress rate is commonly adopted in the formulation. is method is a meshfree nonlocal Lagrangian method, and the resolution of the method can be adjusted with respect to the various control variables
Discussion and Conclusions e presence of multiple sources of potential failure slip surfaces is important for the proper design of slope reinforcement works, slope risk assessment, and decision making related to preventing slope failure. is phenomenon may not be critical for normal simple slopes but will be more important for staged slopes and slopes with complicated geometry and ground conditions
By combining the SPH method and strength reduction technique, it is demonstrated that SPH can simulate the whole slope failure process and identify all the failure slip surfaces. e failure slip surfaces identified by the proposed method agree fairly well with those obtained by LEM through varying different entrance and exit search domains

Summary

Introduction

Smoothed particle hydrodynamics belongs to the category of meshless methods originally proposed by Lucy [26] and Gingold and Monaghan [27] for astrophysics problems. e strain and strain rates are large in SPH, and the use of frame-invariant Eulerian Jaumann stress rate is commonly adopted in the formulation. is method is a meshfree nonlocal Lagrangian method (where the coordinates move with the fluid), and the resolution of the method can be adjusted with respect to the various control variables. E paper starts with a brief introduction to SPH, followed by overviews of FEM- and FDM-based strength reduction techniques used to perform slope stability and to locate the multiple failure slip surfaces in LEM.

Results

Conclusion