Damage and fracture analysis of Dagangshan arch dam under strong earthquake

The theory of energy equivalence and effective stress concept are applied to analyze damage and fracture for Dagangshan high arch dam(210m) and its safety to resist strong earthquake.Damage is considered as irreversiblly internal variable to deal with strength reduce and stiffness degradation for concrete under loading.Damage tensor including characteristic of rate-dependent of concrete and effect of multiaxial stress for structures is used to set up rate-dependent elasto-plastic damage model.Return mapping algorithm is selected to solve stress integral in constitutive equation.Main procedure for finite element program is presented.The dam is simulated numerically to analyze its damage and fracture and is evaluated from the view of safety to resist strong earthquake with peak earthquake acceleration of 0.5575g.The results show that the dam's damage is in low grade and is good in integer after strong earthquake.But some zones of the dam are weak to resist earthquake such as the joint of dam and foundation at the bottom and the top arch of the dam.Meanwhile,strain-rate response is different for each zone of the dam and should not be neglected to strength and deform of concrete.