基于动水及桩－土－结构相互作用的斜拉桥地震响应分析

摘要

为了得到更为符合实际情况的跨江大桥动力稳定性的地震反应分析，在桥梁抗震研究中必须综合考虑动水及桩－土－结构的相互作用。基于此，结合某斜拉桥，采用基于 Morison 方程的动水力简便计算方法来模拟水对桥梁下部结构的动水压力，通过大型有限元程序 Midas ／Civil 分别建立了没有考虑动水及桩土效应和考虑动水及桩土效应两种情形下的计算模型，通过输入 El －Centro 波分析了动水及桩土效应对斜拉桥结构动力特性和地震反应的影响。分析表明动水及桩土效应对斜拉桥动力特性和地震反应的影响较大，因此在对跨江斜拉桥结构进行抗震分析时，应考虑动水及桩土效应对其动力反应的影响。%In order to achieve the better response analysis of river-spanning bridge,the dynamic water and pile-soil-structure interaction are considered.Based on a cable-stayed bridge,use the dynamic hydraulic simple calculation method based on the Morison equation to simulate the dynamic water pres-sure on the lower part of the bridge structure,through the finite element program MIDAS /Civil respective-ly established without the dynamic water and pile-soil-structure interaction and considering the dynamic water and pile-soil-structure interaction the two calculation model of the bridge,through input El centro seismic wave to analysis the dynamic characteristics and seismic response of cable-stayed bridge under the dynamic water and pile-soil-structure interaction.Analysis shows that the dynamic water and the effect of piles and soil influence on the dynamic characteristics and seismic response of cable-stayed bridge is big-ger,so when analysis the seismic of cable-stayed bridge across the river,the effect on its dynamic response by the dynamic water and pile-soil-structure interaction should be considered.