Abstract: For numerical simulation of seismic failure process of concrete dams, a plastic-damage thin- layer element model is proposed within the finite element framework. Based on the principle of deforma ⁃ tion equivalence, the plastic-damage behavior of concrete is concentrated into thin-layer elements in this model. By incorporating thin-layer elements into the high dam-foundation system, a large-deforma ⁃ tion failure analysis model for concrete dams is established. Furthermore, the Coupled Eulerian- La ⁃ grangian method is adopted to simulate reservoir water, so that a fluid-structure interaction model for seismic failure analysis of concrete dams is developed. As a case study, the full-process simulation from small-deformation damage to large-deformation failure of Koyna dam is achieved. The effects of con ⁃ crete constitutive behavior and reservoir water on dam failure are also analyzed.

Key words: plastic-damage, thin-layer element, concrete dam, strong earthquake, large-deformation failure

摘要： 针对混凝土坝强震大变形破坏数值模拟问题，在有限元框架下，应用变形等效原理，将混凝土塑性-损伤行为集中到薄层中，提出了塑性-损伤薄层单元模型。将薄层单元引入高坝-地基系统，建立了混凝土坝大变形破坏分析模型。在此基础上，采用CEL 方法模拟库水，建立混凝土坝大变形破坏流固耦合分析模型。以Koyna 坝为例，实现了小变形-大变形破坏全过程模拟，分析了混凝土材料本构和库水对坝体破坏的影响规律。

关键词: 塑性-损伤, 薄层单元, 混凝土坝, 强震, 大变形破坏