【摘要】 本文采用非线性动力时程分析方法,研究重力坝坝体-地基系统的地震反应;在计算模型中坝基交界面采用非线性接触单元和Lagrange乘子法;分析金安桥重力坝在不同概率水平的实际地震波作用下坝基交界面张开屈服、残余滑动位移、时程最小安全系数以及坝体破损程度,研究接触面的摩擦系数对上述反应量的影响,对比刚性与弹性两种接触模型的安全系数与加速度关系,结果表明两者的均值基本接近。根据反应量的变化规律初步建议坝基交界面地震破损安全评价指标,为重力坝抗震设计与易损性分析提供参考。更多还原

【Abstract】 Seismic stability analysis of a gravity dam-foundation system has been performed by using a nonlinear dynamic procedure.The interface between the dam base and foundation is simulated by contact elements with Lagrangian method in iteration analysis.The yielding and sliding displacements,and the safety factor of timehistories against sliding along the interface and the damage degree(D_M) in the dam monolith are studied for the Jin-anqiao Dam subjected to earthquakes with different probabilities of exceedance recorded at Koyna and Pacoima,etc.It is shown that the responses are sensitive to friction coefficients along the interface.The indexes of damage at the interface,the residual sliding displacements and safety factor histories are given,it provides reference for seismic design and fragility assessment of gravity dams.更多还原