摘要
为研究近、远场地震作用下水动力效应对深水高墩桥梁抗震性能的影响,明确深水高墩桥梁抗震性能分析中考虑动水压力的必要性,以典型的深水高墩大跨连续刚构桥为例,基于OpenSees建立其非线性动力分析模型。通过附加质量法模拟墩-水动力相互作用,并在PEER数据库选择代表性的近场和远场地震动记录,对该桥梁进行不同水深下的非线性地震响应分析,对比研究近、远场地震作用下动水压力效应对深水高墩桥梁抗震性能的影响。研究表明:不论近场还是远场地震作用,墩-水相互作用都会显著增大桥梁结构的地震响应,近场地震作用下,对桥墩的墩顶位移和墩底曲率的改变率分别可达到64.77%和156%;与远场地震作用相比,近场地震作用下墩-水相互作用对深水高墩桥梁抗震性能的影响更为显著,在近场地区的深水高墩桥梁抗震性能分析中,应充分考虑近断层地震动和墩-水相互作用的耦合效应;近场地震作用下,墩-水相互作用主要激起桥墩的一阶振型产生基频共振,增大墩底的损伤,而远场地震作用下墩-水相互作用会激起桥墩的高阶振型,不仅增大墩底的损伤而且会加剧墩身中上部的损伤;深水高墩桥梁抗震性能分析不仅需要考虑动水压力效应,还应考虑近场和远场地震动带来的影响。
In order to study the influence of hydrodynamic effect on the seismic performance of high pier bridges in deep water under near-field and far-field earthquakes,and clarify the necessity of considering dynamic water pressure in the seismic performance analysis of high pier bridges in deep water,this paper takes a typical longspan continuous rigid frame bridge with high piers in deep water as an example to establish its non-linear dynamic analysis model based on OpenSees.The non-linear seismic response analysis of the bridge under different water depths is carried out by simulating the pier-hydrodynamic interaction through the added mass method,and representative near-field and far-field ground motion records are selected from the PEER database to compare and study the influence of dynamic water pressure effect on the seismic performance of high pier bridges in deep water under near-field and far-field earthquakes.The research shows that no matter under nearfield or far-field earthquakes,the pier-water interaction will significantly magnify the seismic response of the bridge structure.Under near-field seismic action,the change rates of pier top displacement and pier bottom curvature can reach 64.77% and 156% respectively;compared with far-field seismic action,pier-water interaction has a more significant impact on the seismic performance of high pier bridges in deep water under near-field seismic action.The coupling effect of near-fault ground motion and pier-water interaction shall be fully considered in the seismic performance analysis of high pier bridges in deep water in near-field areas;under the near-field seismic action,the pier-water interaction will mainly excite the first-order vibration mode of the pier to generate fundamental frequency resonance and increase the damage to the pier bottom,while under the far-field seismic action,the pier-water interaction will excite the higher-order vibration mode of the pier,which will not only increase the damage to the pier bottom but also intensify the damage to the
作者
李明
开永旺
Li Ming;KAI Yongwang(School of Rail Transit,Zhejiang Institute of Communications,Hangzhou Zhejiang 311112,China;School of Road&Bridge,Zhejiang Institute of Communications,Hangzhou Zhejiang 311112,China)
出处
《中国铁路》
北大核心
2024年第1期57-66,共10页
China Railway
基金
浙江省自然科学基金项目(LY18E080002)。
关键词
高墩桥梁
动水效应
抗震性能
近、远场地震
high pier bridge
hydrodynamic effect
seismic performance
near-field and far-field earthquakes
