中文摘要：

以裂缝状态下辽宁葠窝水库混凝土重力坝为研究对象,选用混凝土弥散裂缝本构模型,模拟强震下坝体裂缝产生与破损的全过程;利用耦合的拉格朗日-欧拉有限元分析法,描述库水-坝体-基岩动力耦合非线性效应,建立了溢流坝段地震反应分析三维有限元模型。通过对数值模型输入El Centro波,考虑库水水位变化状况,分析了溢流坝段强震响应规律与破坏特征,据此评价溢流坝段的强震安全性。分析表明：由于坝体先期存在的裂缝影响,坝踵区、坝趾区、牛腿区及闸墩与溢流堰交汇区均易发生开裂破坏;先期存在的裂缝与混凝土老化及结构劣化,显著降低了闸墩的整体刚度、消弱了坝体局部强度,增大了溢流坝段的动力反应。

英文摘要：

This study investigated the concrete gravity dam of the Liaoning Shenwo reservoir using a concrete dispersion crack constitutive model to simulate the process of cracking and breaking of the dam during a strong earth- quake. The coupled Lagrangian-Eulerian finite element analysis method was used to describe the nonlinear effects of dynamic coupling of the reservoir water, dam, and bedrock. A 3D finite element model was used for the seismic reaction analysis of the overflow dam section. By inputting an E1 Centro wave into the numerical model and measuring the changes in the reservoir water level, the response law and damage characteristics of the overflow dam section under strong earthquake conditions were analyzed. This was used to evaluate the safety of the overflow dam during strong earthquakes. Cracking occurred at the dam heel, dam toe, bracket area, and the junction of the pier and the overflow weir because of the existing crack in the dam. Because of the existing cracks, concrete aging, and structural deterioration, the overall stiffness of the piers has reduced significantly, the strength of some parts of the dam has been weakened, and the seismic response of the overflow dam section has increased significantly.