| Citation: | Guo Youjun, Liu Xinlong, Shi Zhenming, Cao Chuanghua, Xia Chengzhi, Lu Guangyin, 2025. An Improved SPH Method Based on Strength Reduction to Simulate Entire Process of Joint Slope Failure. Earth Science, 50(10): 4009-4026. doi: 10.3799/dqkx.2025.201 | 
The instability of fractured rock slopes is a major geological disaster, and its failure involves the coupling process of crack initiation, propagation and slip. Traditional numerical methods are unable to simultaneously simulate continuous fracture and discontinuous contact, and they have limitations such as grid distortion and complex parameter calibration. A three-dimensional SPH algorithm based on strength reduction and kernel function improvement is developed to simulate the entire process of fracture, crack propagation and contact slip of three-dimensional fractured rock mass slopes. In the improved three-dimensional SPH method, the determination of crack germination was achieved through strength reduction and the Mohr-Coulomb violation criterion with tensile truncation. The crack propagation of rock mass was realized by introducing damage marks in the improved kernel function. Subsequently, the three-dimensional contact criterion of damage particle dots was introduced to construct the three-dimensional contact force between intact particles and fractured particles. Firstly, three-dimensional uniaxial compression tests were adopted to verify the feasibility of the algorithm, and the brittle fracture characteristics of single-fracture rock masses with different inclinations were determined. Subsequently, the improved SPH method and the strength reduction theory were applied to multi-joint rock slopes considering different joint inclination angles to simulate the failure process of three-dimensional fractured rock landslides and evaluate their stability. The research results show that the improved SPH method based on strength reduction has the advantages of high computational efficiency, less parameter calibration and high accuracy in simulating the failure and stability of three-dimensional fractured rock slopes. Moreover, this method can be used to evaluate the stability of other rock slopes with structural planes.
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