Numerical research on the progressive failure of gravity dam foundation rock mass based on damage theory

Currently, researches on the gravity dam deep and shallow anti-sliding stability mainly focus on the analysis method and instability criterion, while the studies on specifically test the breakage of gravity dams due to weakening foundation rock mass and structural planes under loading are rare. With damage mechanics theory, a numerical model, considering the nonuniformity properties of rock materials, has been established to analyze the breakage process of dam foundation rock mass. Taking the No.3 non overflow dam section at left bank of the Three Gorges Dam as the research case, the damage process of the dam foundation was simulated dynamically. The development of damage zone and the distribution of different damage extent were both presented, and the safety status of global stability was analyzed. The obtained results show that they are in consistent with model test results, indicating the reliability of the established damage model, which can be used to analyze the breakage mechanism of rock mass and evaluated the safety of anti-sliding stability.