节点文献
多维多点激励下连续刚构桥地震反应分析
Seismic Response Analysis of Continuous Rigid-Frame Bridge under Multi-Dimension and Multi-Support Excitation
【作者】 宫成武；
【作者基本信息】 哈尔滨工业大学 ， 结构工程， 2008， 硕士
【摘要】 桥梁结构是公路、铁路等交通系统的重要设施,而地震则是危害人类社会的一大自然灾害。每次大的地震都会使桥梁结构遭受到不同程度的破坏,造成了巨大的经济损失和人员伤亡。现有的桥梁设计规范通常只考虑一致地震动输入并通常基于刚性地基假定,而实际上,众多研究表明,在进行桥梁抗震设计时,考虑地震动的多维多点输入及土-桩-结构动力相互作用效应才更接近于桥梁的实际工作状态。本文在桥梁抗震理论和土-桩-结构动力相互作用理论研究的基础上,结合重庆广阳岛大桥工程实例,系统地研究了桥墩高差和土-桩-结构动力相互作用对多维多点激励下连续刚构桥地震反应的影响。基于刚性地基假定,采用桥梁有限元分析专用软件MIDAS/civil,建立了四个桥墩高差不同的连续刚构桥有限元模型,并选取了1978年MIYAGI-Coast地震记录和台站CWB99999 HWA005、台站CWB99999 HWA032所记录到的1999年台湾集集地震记录分别作为地震动输入,对四个模型进行了动力时程分析,研究了桥墩高差和行波效应对连续刚构桥地震反应的影响。采用改进的Penzien集中质量模型,并将其扩展到三维空间,建立了考虑土-桩-结构动力相互作用效应的计算模型,比较了墩底固结模型和考虑土-桩-结构动力相互作用模型的动力特性的差异;采用MIYAGI-Coast地震记录和两个台站所记录到的台湾集集地震记录,计算得到了考虑土-桩-结构动力相互作用模型中的结构内力响应,并与墩底固结模型中的结构内力响应做了对比分析,研究了土-桩-结构动力相互作用对多维多点激励下连续刚构桥地震反应的影响。
【Abstract】 Bridges are vital elements of transportation systems, such as highway system and railway system. The great earthquakes will cause severe damage for bridges, and result in huge economic losses and life casualties. The uniform seismic excitation and rigid foundation model of bridges are specified in most existing seismic design codes. In fact, a lot of researches have showed that it is more rational to consider the multi-dimension and multi-support seismic excitation and soil-pile-bridge dynamic interaction in seismic analysis of bridges.The basic seismic theory of bridges is introduced in this study. Based on the Guangyang Dao Bridge, the effects of height difference of piers and soil-pile-bridge dynamic interaction are investigated on the seismic response of continuous rigid-frame bridge subjected to multi-dimension and multi-support excitation.By using MIDAS/Civil program, four finite element models of rigid foundation with different height difference of piers are established. The effects of height difference of piers and traveling wave are studied on continuous rigid-frame bridge. Here the MIYAGI-Coast, CWB 99999 HWA005 and CWB99999 HWA032 record are used in this study.Based on the improved Penzien model, the bridge model considering soil-pile-bridge dynamic interaction is established. The discussion is conducted on the difference of dynamic characteristics of bridge considering and not considering soil-pile-bridge dynamic interaction.With the MIYAGI-Coast record and two records from Chi-chi earthquake, the seismic response of bridge considering soil-pile-bridge dynamic interaction are analyzed. And the effect of oil-pile-bridge dynamic interaction is investigated on the continuous rigid-frame bridge under multi-dimension and multi-support excitation.