摘　要：采用塑性损伤力学对混凝土重力坝进行非线性动力分析，通过研究塑性损伤本构中滞回曲线的特点以及地震中重力坝裂缝发展特征和结构能量耗散机理，建立了包含能量特性的大坝整体损伤评价指标。通过分析发现强震作用下坝体上部的损伤是结构的主要损伤，地震中的能量以结构阻尼耗散能量为主，混凝土损伤和塑性耗散的能量所占比例不大，但与裂缝的发展有直接关系。提出的大坝整体损伤指标可以综合的反应结构的整体损伤程度，以此对结构进行抗震设计，可以提高结构的抗震性能。

Abstract: Nonlinear seismic analysis of concrete gravity dam is performed based on the plastic damage theory. The hysteretic characters, energy dissipation ability, failure mechanism and characteristics are researched. A seismic damage assessment model which can consider damage energy dissipation is developed for describing the damage degree of dams during strong earthquakes. The results show that the dam head are the vulnerable parts of gravity dam. The vibration energy and the earthquake responses of structure are reduced effectively by the structural damping, little amount seismic energy is dissipated by concrete damage and plastic dissipation. The seismic damage assessment model can quantitatively evaluate the damage degree of gravity dams during strong earthquake.