Analysis method of water inrush for tunnels with damaged water-resisting rock mass based on finite element method-smooth particle hydrodynamics coupling

Abstract

During drilling and blasting construction, a water inrush can be caused by damage to a water-resisting rock mass. Tunnel water inrush is a common anthropogenic geological hazard in engineering. The traditional finite element method (FEM) is less accurate in dealing with large deformation problems, and the Discrete element method (DEM) cannot realize engineering scale operation. In this study, the Johnson-Holmquist damage constitutive model was adopted, based on the LS-DYNA secondary development technology. A fluid grid was used in the blast damage area, and smooth particle hydrodynamics (SPH) were introduced to simulate the fluid. The far area of the tunnel is calculated by solid grid, forming a coupled algorithm of FEM and DEM. Based on a case study of the Yonglian Tunnel, this study simulated the evolution of a tunnel water inrush under the action of blasting. Through contrastive analysis, the numerical simulation results for the water inrush owing to damage to the water-resisting rock were found to correspond to those found using field tests. Therefore, this method can provide reference for underground engineering construction.