高烈度山区不同地形下常规桥梁地震响应分析  

Seismic Response Analysis on Conventional Bridges in Different Terrains of Mountainous Areas with High Intensity

作　　者：叶洪波 张哲[2] YE Hongbo;ZHANG Zhe(Henan Provincial Communications Planning,Survey&Design Institute Co.,Ltd.,Zhengzhou 450018;School of Civil Engineering,Zhengzhou University,Zhengzhou 450000)

机构地区：[1]河南省交通规划设计研究院股份有限公司,郑州450018 [2]郑州大学土木工程学院,郑州450000

出　　处：《公路交通技术》2024年第2期106-115,共10页Technology of Highway and Transport

基　　金：国家自然科学基金项目(51478437)。

摘　　要：高烈度地震山区高速公路桥梁受复杂地形条件限制常设在深沟河谷或陡坡半填半挖处,不同地形处桥梁的地震响应和损伤机理可能不一致。为研究地形因素和结构抗震体系对桥梁地震响应及损伤机理的影响,将山区地形总结为3类典型地形,基于有限元软件Midas Civil并依托在建项目分别建立各地形处采用延性抗震体系和减隔震体系的装配式预应力混凝土T梁桥有限元模型,利用地震动加速度记录对桥梁进行非线性动力时程分析。结果表明:1)高烈度震区桥梁地震响应受地形和抗震体系影响显著,桥梁抗震性能表现为“W”型地形>“槽”型地形>“V”型地形,减隔震体系>延性抗震体系;2)当联内平均墩高大于32 m时,桥梁采用减隔震体系可能失效,是否失效与相邻联的刚度有关,相邻联刚度越小,失效概率越大;3)设置横向高低墩可使墩底横桥向剪力减小、使顺桥向弯矩增大、使同一盖梁下矮墩更易遭受破坏。Highway bridges in mountainous areas with high intensity earthquake limited by complex terrain conditions are permanently located in deep ravines,river valleys or half-filled and half-excavated steep slopes,and the seismic response and damage mechanisms of bridges in different terrains may be inconsistent.In order to study the influence of terrain and structural seismic design on the seismic response and damage mechanism of bridges,the mountainous terrain is summarized into three types of typical terrain,based on the finite element software Midas Civil and the projects under construction,the finite element models of prefabricated pre-stressed concrete T-beam bridges with ductile seismic system and seismic isolation system were established respectively,and the nonlinear dynamic time history analysis of the bridge is carried out by ground acceleration recording.The results show that:1)The seismic response of bridges in high seismic intensity areas is significantly affected by the terrain and seismic system,and the seismic performance of bridges is as follows:"groove"type terrain>"W"type terrain>"V"type terrain,seismic isolation system>ductility seismic system:2)When the average pier height in the tandem is greater than 32 m,the bridge may fail using the seismic isolation design,and the failure is related to the stiffness of the adjacent link,i.e.the smaller the stiffness of the adjacent link,the greater the probability of failure;3)Setting the transverse high-low piers can reduce the shear force of the cross bridge at the bottom of the pier,increase the bending moment along the bridge,and make the low pier under the same cover beam more vulnerable to damage.

关 键 词：高烈度震区 延性抗震体系 减隔震体系 山区地形 

分 类 号：U442.55[建筑科学—桥梁与隧道工程]