Simulation analysis theory and experimental verification of air-cushion isolation control of high concrete dams

Abstract

To focus on the key scientific problem of process control of dynamic catastrophe of high dams, presented for the first time are the modelling theory of liquid-gas-solid tri-phase coupling of the air-cushion isolation control of high dams and its numerical simulation method, and theoretical description of the complicated dynamics problem of the tri-phase coupling-thermodynamics state-material-contact bi-nonlinearity, as well as the simulation analysis of the key effects of dynamic catastrophe of the air-cushion isolated high dam engineering. The analytic solution of plane-wave with rigid-dam body was created. The simulation comparison of dynamic catastrophe processes of 305 m Jinping arch dam with and without seismic control was carried out, and the results were basically in agreement with that obtained from the large shaking table tests, and verify each other. The entire air-chamber and optimized air-cushion with varying thickness were presented to develop a optimization method. The large shaking table tests of the isolated dam model, which is satisfied with the basic dynamic similarity relations, were performed for the first time. The test data seemed to be convincing and were in agreement with the dynamic simulation results of the tested model, thereby providing an experimental verification to the simulation theory and method. The combination experiments of theoretical model and physical model demonstrated that the hydrodynamic pressure of high arch dams can be reduced by more than 70% as well as the first and third principle stresses of the dam body reduced by more than 20%–30%, thereby the global anti-seismic capacity of the high dam being improved significantly. The results have shown that the air-cushion isolation is the prior developing direction of structural control technology of high concrete dams.