Numerical simulation on the stability of rock slope based on an improved SPH Method

The presence of random fissures has a great impact on rock slope stability. To investigate the failure modes and stability of rock slopes containing different types of pre-existing fissures, the fracture mark ξ was introduced to improve the kernel function in the traditional smoothed particle dynamics(SPH) method, and a novel numerical method, the improved kernel of smoothed particle hydrodynamics(IKSPH), was proposed to realise the microscopic damage characteristics of particles. The ‘random fissure generating method’ has been proposed for random fissure generation, and the gravity increase method has been embedded into the IKSPH program, thereby realising the stability analysis of rock slopes considering crack propagation processes. A typical steep rock slope is taken as a numerical simulation example considering the random distributions of preexisting fissures, and its failure modes as well as the stability under different conditions were simulated. The results show that the failure processes of the rock slope contain propagations of microcracks and then macrocrack penetrations. When the fissure length is short, shallow collapse failure modes can be observed; when the fissure length is long, the deep layer slide occurs, and the slope stability decreases with an increase in fissure length. The micro and macrocrack surfaces are basically consistent with pre-existing fissure angles, and the safety factor is the least at a fissure angle of 30°. The greater the fissure density, the greater the number of macrocracks, and the stability decreases with an increase in the number of pre-existing fissures. The research results can provide some references for disaster protection and understanding the failure laws of rock slopes. Meanwhile, combining the geological survey results with the numerical simulations and developing a high-performance IKSPH program will be a future research direction.