【摘要】 地震作用下横缝的张开、闭合与滑移对高拱坝的动力响应有着显著的影响,而横缝的张开度是有横缝拱坝抗震分析的一个重要计算指标。结合实际工程,采用有限元混合法模拟横缝的非线性行为,用多次透射人工边界条件计及无限地基的辐射阻尼效应,给出三种库水模型及其数值求解方案,考查不同库水模型对高拱坝横缝开度的影响。计算表明,忽略水体的可压缩性将引起显著的计算误差,横缝最大张开度不但幅值不同,沿坝轴线方向的分布也有较大差异。附加质量模型和忽略水体的可压缩性将过分夸大库水对坝体的作用,在计算中应该考虑库水的可压缩性。更多还原

【Abstract】 Contraction joints play an obvious role in the nonlinear response of high arch dams to strong earthquakes through opening,closing and sliding,and joint opening is a basic index of seismic analysis of arch dams with contraction joints.This paper adopts a mixed finite element method to simulate the nonlinear behavior of the joints for a practical project.Three reservoir models of different numerical schemes are used to analyze the dynamic characteristics of high arch dams,with the foundation radiation damping accounted by an artificial multi-transmitting boundary condition and different joint opening models,are studied.Results show large errors of the models that neglect water compressibility.Amplitude of the maximum joint opening and its distribution along the dam axis are quite different from the compressible case,and the Westergaard formulation or the incompressible model exaggerates the effect of water pressure.Compressible model is recommended for a dynamic analysis of high arch dams.更多还原