【摘要】 为了研究混凝土重力坝在地震动荷载作用下的潜在失效模式,以金安桥碾压混凝土重力坝5号非溢流坝段为例,运用粘弹性边界法和流固耦合法建立了反映重力坝在地震动作用下动力响应特征的坝体-地基-库水抗震分析模型。基于增量动力分析(IDA)法:绘制了以相对位移转角为x轴(损伤指标,DM)和峰值地面加速度为y轴(强度指标,IM)的IDA曲线簇;分析了金安桥大坝在极端荷载作用下的潜在失效模式和其在不同峰值地面加速度下重力坝的损伤破坏过程。结果表明:金安桥大坝在地震动荷载作用下,可能发生功能失效的地方多出现在坝体折坡处、碾压分区交界处、坝踵与坝基交界处、廊道顶等应力集中处。因此,加强对这些区域的抗震防护有利于提高大坝整体的抗震水平。更多还原

【Abstract】 In order to study the potential failure modes of concrete gravity dam under seismic load,the No. 5 non-overflow dam section of Jin’anqiao roller compacted concrete( RCC) gravity dam is taken as a study example.Based on viscous-spring boundary method and fluid-solid coupling method,a seismic analysis model of dam bodyfoundation-reservoirwater interaction system is established to reflect the dynamic response characteristics of gravity dam under ground motion. Based on incremental dynamic analysis( IDA) method,the IDA curve with relative displacement rotationas x-axis( damage measure,DM) and peak ground acceleration as y-axis( intensity measure,IM)are obtained. The potential failure modes of Jin’anqiao dam under extreme loads and the process of damage of gravity dam under different peak ground acceleration are studied. It is concluded that under the ground motion load,the places where functional failure may occur are mostly found in the stress concentration of the dam slope,such as the boundary of the rolling section,the junction of the dam and the dam foundation,and the top of the corridor. Therefore,strengthening the seismic protection of these areas is conducive to improve the overall aseismic level of the dam.更多还原