高墩深水大跨度连续刚构桥非一致地震响应分析

Seismic Response Analysis of Long-Span Continuous Rigid-Frame Bridge with High-Rise Piers in Deep Water under Non-uniform Seismic Excitation

讨论了高墩深水大跨度连续刚构桥的地震响应分析。提出一种适用于计算深水桥墩的地震动水压力公式,在有限元模型中采用附加质量的方法计入该作用,并考虑非一致激励和桩土耦合对桥梁结构的作用,并对不考虑动水压力和考虑动水压力工况进行比较。分析表明,考虑动水压力时的地震反应内力和位移比不考虑动水压力时的地震反应内力和位移大。分析结果可以为连续刚构桥的抗震设计提供参考。

The non-uniform seismic response of long-span continuous rigid-frame bridge with high-rise pier in deep water is discussed. Based on the characteristics of high-rise pier in deep water,a formula applicable to calculating seismic hydrodynamic pressure of deep water pier is worked out. And the added mass method is adopted in the finite element model to evaluate the effect of hydrodynamic pressure during earthquakes. The non-uniform excitation and pile-soil interaction are also taken into account during the analysis. Aided by general finite dement software ANSYS ,a non-uniform excitation time-history response analysis on certain continuous rigid-frame bridge is taken as an example to verify the proposed method. The two analytical results are compared in the cases of hydrodynamic pressure and without hydrodynamic pressure. It shows that the internal force and displacement of seismic response are bigger when considering the hydrodynamic pressure than that in the case without considering the hydrodynamic pressure. This can provide reference to the seismic design of continuous rigidframe bridge.