Time-dependent virtual crack model of rock with application to slope stability

Time-dependent deformation of rock involves the continuous to discontinuous deformation of joints, cracks, holes, and other defects under long-term stress conditions. Thus, it is of great significance to investigate the correlation between internal crack propagation in rock and external time-dependent damage and failure of rock to better understand the long-term stability of engineering rock mass. Here, we put forward a time-dependent virtual crack model to achieve the entire continuous-discontinuous time-dependent deformation progress of rock from the microscopic to the macroscopic scale. Simulated stress-strain curves for granite, including the mode of failure (axial splitting and Brazilian splitting), agree well with experimental data. We also used the virtual crack model to study the stability of one of the slopes of the Xiaowan Hydropower Station (China). The simulation results indicate that the weakly disturbed zone is the potential sliding surface, and that the defor-mation of the slope is similar to in-situ measurements. In the model, the vertical displacement decreased by 500 mm in 180 days and the axial strain rate decreased from 25 mm/d to zero, suggested that the slope is currently stable.