基于变截面结构的预应力连续刚构桥地震响应分析  

Seismic response analysis of prestressed continuous rigid frame bridges with variable cross-section structures

作　　者：游宏炎 You Hongyan(Fujian Xingyi Transportation Technology Co.,Ltd.,Nanping Fujian 354300,China)

机构地区：[1]福建兴夷交通科技有限公司,福建南平354300

出　　处：《山西建筑》2024年第23期176-179,183,共5页Shanxi Architecture

摘　　要：预应力刚构桥具有结构牢固、跨度大、施工周期短的优点,但在抗震方面属于该类桥梁的薄弱点,基于此,以某变截面结构形式的预应力刚构桥工程为例,设计了不同角度的地面震源方案,采用典型EI-Centro地震波建立有限元分析模型,对不同地震波角度下的响应特征、位移时程及频谱分布展开研究。研究结果表明:在顺桥向地震波的作用下,主梁结构横桥向几乎不产生位移,而竖向位移的数值最大;在横桥向地震波的作用下,顺桥向及竖向几乎不产生位移,而桥梁倾覆的现象较为明显,最大位移值达到104.61 mm,应力值均出现在主梁跨中位置及桥墩底部;随着地震波与顺桥向夹角的不断增大,横桥向位移不断增大,增大速率逐渐减小,随着地震频率的不断提高,动位移发展较快的频率区间基本集中在0.8 Hz~1.6 Hz之间,动位移基本在0.928 Hz频率位置处达到最大峰值。Prestressed rigid frame bridges are known for their structural solidity,large span,and short construction period.However,they have a in seismic resistance.This paper addresses this issue by using a specific variable cross-section prestressed rigid frame bridge project as an example.We designed different ground seismic source and used the typical EI-Centro earthquake wave to establish a finite element analysis model.We then studied the response characteristics,displacement history,and frequency distribution under earthquake wave angles.The results show that under the action of the earthquake wave along the bridge direction,the main beam structure hardly displaces in the transverse direction the bridge,while the maximum displacement occurs in the vertical direction.Under the action of the transverse earthquake wave,there is almost no displacement in the bridge direction vertical direction,but the bridge shows a noticeable overturning phenomenon,with the maximum displacement reaching 104.61 mm.The stress values mainly appear the midspan of the main beam and the bottom of the pier.As the angle between the earthquake wave and the bridge direction increases,the transverse displacement increases but the increase rate gradually decreases.As the earthquake frequency increases,the frequency range with rapid development of dynamic displacement is mainly concentrated between 0.8 Hz and 1.6 Hz,and the dynamic displacement reaches its maximum peak at around 0.928 Hz.

关 键 词：预应力 刚构桥 地震响应 时程分析 

分 类 号：TU997[建筑科学—市政工程] U448.23[建筑科学—桥梁与隧道工程]