The project of high arch dam has an intense disturbance to its geological environment with high in-situ stress in the critical instability state, and the creep and damage of foundation rock mass resulting from the process of non-equilibrium evolution has an adverse impact on long-term safety of arch dam. Time-dependent deformation reinforcement theory (TDRT) has been presented for evaluating the long-term stability of arch dam. Based on Duvaut-Lions visco-plastic model and Lyapunov asymptotic stability analysis, the principle of minimum plastic complementary energy is proved for perfect and hardening yielding, in which viscoplastic structures deform tending to the limit steady state at which the PCE is minimized under time invariant loading and boundary conditions. So the PCE is a reasonable and quantitative criterion for stability evolution and unbalanced forces can be used to determine the reinforcement since they have a complete mathematical basis. The expression of PCE and unbalanced forces for finite element method have been finished base on Drucker-Prager yield criteria. This theory is implemented in TFINE, which is a parallel FEM code with GPU acceleration, and then used in the long-term safety evaluation of Jinping arch dam in China.
In China, most of high arch dams are located in the southwest, such as Jinping I Hydropower Station with the maximum height of 305 m, Xiaowan Arch Dam (294.5 m), Xiluodu Arch Dam (285.5 m), etc. Due to the intensively geological uplifting of the Qinghai-Tibet Plateau, this region has steep valley and complicated geological environment with high in-situ stress in the critical instability state. The engineering experiences and catastrophes of arch dams around the world have shown that the stability of dam foundation is the key point of the overall stability of the dam , so the special geological conditions of the Southwest China result in a prominent problem of the stability of high arch dam.