Failure and Stability Analysis of Jinping-I Arch Dam Based on Geomechanical Model Test and Nonlinear Numerical Analysis

Jinping-I high arch dam is the highest arch dam (305 m) in the world, but the topography of its left and right sides of the arch is not symmetrical, which has a great impact on the overall stability of the arch dam. Based on the geomechanical model test and nonlinear numerical simulation, the evolution processes of cracks and failure during overloading in dam body and faults are demonstrated. Three safety factors of Jinping-I are gained and compared with other high arch dams. The safety factor of crack (K1) is 2.5, the factor of initial nonlinear deformation (K2) is 4.5 and the factor of the ultimate bearing capacity (K3) of Jinping-I is 7.5, indicating that the project has a high inherent safety. Treatments of foundation and weak zones are proved to be effective and then suggestions for reinforcement are given. Additionally, the relationships between model test and numerical simulation based on the deformation reinforcement theory are studied, which verifies that the unbalanced force is an effective indicator for cracking.