Dynamic Damage Analysis Of High Concrete Dams Based On ABAQUS

As an important part of the national energy strategy, there will be constructed quite a few world-class high concrete dams in the southwestern region. Because of the strong earthquake in the western region, the research for aseismic safety evaluation and catastrophe process of the concrete dams is necessary. The purpose of this paper is to get not only the dynamic response but also the damage distribution and the generation and development of cracks. The domestic high arch dam and gravity dam subjected to designed strong earthquake are analyzed based on the concrete damaged plasticity model embedded in the finite element analysis software ABAQUS. Tensile damage distribution and the time history of typical elements’damage factor are acquired. This study reveals the weak parts of the dam for aseismic evaluation and the occurrence and development process of dam damage, and would provide an analytical approach to aseismic safety analysis of high concrete dams. The contents of this paper include the following three aspects:(1) Not only the fundamental of finite element method but also the establishment of dynamic equation and the basic concepts of damage mechanics are introduced briefly. The concrete damaged plasticity model embedded in the finite element analysis software ABAQUS and model parameters are introduced.(2) The finite element model of a domestic high arch dam is established. Modal analysis is completed to obtain natural frequencies and mode shapes. The linear elastic and nonlinear numerical simulations for arch dam are completed under the combination load case of gravity and earthquake. Not only acceleration and displacement envelope diagram but also the first principal stress envelope diagram are extracted along arch axis on the top of dam and along crown cantilever. Two kinds of envelope diagram with the linear elastic and nonlinear constitutive model are compared. The time history of typical elements’ damage factor is extracted. Tensile damage distribution on upstream and downstream faces and damage distribution in cross sections perpendicular to z-axis and x-axis are acquired. This paper attempt to reveal the occurrence and development process of cracks of high arch dam.(3) The finite element model of a high gravity dam in the western region is established. Modal analysis is completed to obtain natural frequencies and mode shapes. The linear elastic and nonlinear numerical simulation for gravity dam are completed under the combination load case of gravity and earthquake. Not only the time history of acceleration and displacement but also the time history of the first principal stress are extracted at the key location, such as dam heel and dam toe. Two kinds of output variables with the linear elastic and nonlinear constitutive model are compared. Tensile damage distribution on upstream and downstream faces and damage distribution in cross sections perpendicular to z-axis and x-axis are acquired. This paper attempts to reveal the occurrence and development process of cracks of high gravity dam and compare numerical simulation with model test.