中文摘要：

为了研究地震作用下动水压力对深水桥墩的影响,以声波动理论为基础,通过对流体域边界条件的简化和流体域范围的探讨,建立了一种改进的墩-水耦合有限元模型,并提出了常用深水桥墩的理想流体域范围图。分别讨论了深水桥墩在简谐荷载、地震荷载作用下的动力响应,结果表明：动水压力增大了桥墩的动力响应,增幅在20%到50%之间,不可忽视;当桥墩基频越接近简谐荷载激励频率或地震波主频有效带宽区间时,动水压力的影响越大。

英文摘要：

In order to calculate the effect of hydrodynamic pressure on submerged piers under earthquake,a modified finite element model of pier-water interaction has been proposed.This model,which is based on acoustic theory,is built after simplification of fluid boundary condition and study of fluid scope.An appropriate water scope figure is suggested for commonly used deep-water piers.Then the dynamic responses of the deep-water piers under harmonic loads and earthquake loads are discussed respectively.Results show that the hydrodynamic pressure increases the dynamic responses,the resulting increments are from 20% to 50%,which could not be ignored.When the first order frequency of pier is close to the excitation frequency of harmonic loads or earthquake＇s main frequency effective bandwidth district,the increments of hydrodynamic pressure are greater.