近断层地震动下多跨简支梁桥地震响应及减震研究

兰州理工大学学报 ›› 2024, Vol. 50 ›› Issue (4): 103-111.

近断层地震动下多跨简支梁桥地震响应及减震研究

李旺平^*, 杨雄, 焦应乾, 裴银海, 石岩

兰州理工大学土木工程学院, 甘肃兰州 730050

收稿日期:2021-05-19 出版日期:2024-08-28 发布日期:2024-08-30
通讯作者: 李旺平(1983-),男,甘肃省天水人,博士,副教授.Email:lwp_136@163.com
基金资助:
国家自然科学基金(51908265,51768042)

Study on seismic responses and mitigation of multi-span simply supported beam bridges under near-fault ground motions

LI Wang-ping, YANG Xiong, JIAO Ying-qian, PEI Yin-hai, SHI Yan

School of Civil Engineering, Lanzhou University of Technology, Lanzhou 730050, China

Received:2021-05-19 Online:2024-08-28 Published:2024-08-30

摘要/Abstract

摘要： 为研究近断层地震动下多跨简支梁桥的地震响应及其减震措施,以1座4跨简支梁桥为研究对象,选取3组分别考虑滑冲效应、向前方向性效应及无脉冲效应的近断层地震动和1组远断层地震动作为输入,分析主梁、桥墩和支座等的响应和损伤.发现速度脉冲型近断层地震动对桥梁纵横向的位移均有放大作用,既会增加桥墩和支座的损伤程度,也会增加梁间纵向碰撞次数和碰撞力峰值.为此提出“防屈曲支撑(BRB)+粘滞阻尼器”的组合减震系统,并对粘滞阻尼器的布置形式和参数对减震效果的影响进行了分析.结果表明:该减震方案可有效降低桥墩和支座的损伤、减小主梁纵向位移;且阻尼器布置在主梁与桥台间更有利于减震控制;建议粘滞阻尼系数C梁间取3 000 kN·s/m,台梁间取4 000 kN·s/m,速度相关系数α取0.4.

关键词: 简支梁桥, 近断层地震动, 地震响应, 组合减震系统, 损伤控制

Abstract: In order to study the seismic response and mitigation measures of a multi-span simply suppor-ted beam bridge under near-fault ground motion,a 4-span simply supported beam bridge was taken as theresearch object.Three groups of near-fault ground motions were selected,which respectively considerfling step effect,forward directivity effect,and no pulse effect,along with one group of far-fault seismicmotions for comparison.The seismic response and damage degree of key components such as main beams,piers,and bearings.It was found that the velocitypulse-type near-fault ground motion amplifies the displacement response in both longitudinal and trans-verse bridges,which not only increases the damage degree of the piers and bearings,but also increases thenumber of longitudinal collisions between beams and the peak value of collision force.Therefore,a com-bined seismic reduction system of Buckling-Restrained Brace(BRB)and viscous damper was put forward.The influence of the arrangement and parameters of a viscous damper on the seismic reduction effect is an-alyzed.The results show that the mitigation scheme effectively reduces the damage to piers and bearingsand reduces the longitudinal displacement of main beams.Arranging dampers between the main beam andits abutment is more conducive to the seismic control of a multi-span simply supported beam bridge.It issuggested that the viscous damping coefficient C between the main beams should be 3 000 kN·s/m,whilethe viscous damping coefficient C between abutment and main beams should be 4 000 kN·s/m,with thevelocity correlation coefficient a of 0.4.

Key words: simply supported bridge, near-fault ground motion, seismic response, combined seismic reduction system, damage control

中图分类号:

U448.21

李旺平, 杨雄, 焦应乾, 裴银海, 石岩. 近断层地震动下多跨简支梁桥地震响应及减震研究[J]. 兰州理工大学学报, 2024, 50(4): 103-111.

LI Wang-ping, YANG Xiong, JIAO Ying-qian, PEI Yin-hai, SHI Yan. Study on seismic responses and mitigation of multi-span simply supported beam bridges under near-fault ground motions[J]. Journal of Lanzhou University of Technology, 2024, 50(4): 103-111.

参考文献

[1] 陈乐生.汶川地震公路震害调查:桥梁 [M].北京:人民交通出版社,2012.
[2] 王东升,郭迅,孙治国,等.汶川大地震公路桥梁震害初步调查 [J].地震工程与工程振动,2009,29(3):84-94.
[3] 庄卫林,刘振宇,蒋劲松.汶川大地震公路桥梁震害分析及对策 [J].岩石力学与工程学报,2009,28(7):1377-1387.
[4] KALKAN E,KUNNATH S K.Effects of fling step and forward directivity on seismic response of buildings [J].Earthquake Spectra,2006,22(2):367-390.
[5] YANG S,MAVROEIDIS G P.Bridges crossing fault rupture zones:a review [J].Soil Dynamics and Earthquake Engineering,2018,113:545-571.
[6] 贾宏宇,杨健,郑史雄,等.跨断层桥梁抗震研究综述 [J].西南交通大学学报,2021,56(5):1075-1093.
[7] PARK S W,GHASEMI H,SHEN J,et al.Simulation of the seismic performance of the Bolu Viaduct subjected to near-fault ground motions [J].Earthquake Engineering and Structural Dynamics,2004,33(13):1249-1270.
[8] BESSASON B,HAFLIDASON E.Recorded and numerical strong motion response of a base-isolated bridge [J].Earthquake Spectra,2004,20(2):309-332.
[9] JÓNSSON M H,BESSASON B,HAFLIDASON E.Earthquake response of a base-isolated bridge subjected to strong near-fault ground motion [J].Soil Dynamics and Earthquake Engineering,2010,30(6):447-455.
[10] 汤虎,李建中,邵长宇.中小跨径板式橡胶支座梁桥横向抗震性能 [J].中国公路学报,2016,29(3):55-65.
[11] SHI Y,ZHONG Z W,QIN H G,et al.Toggle buckling-restrained brace systems and a corresponding design method for the seismic retrofit of bridge bents [J].Engineering Structures,2020,221:110996.
[12] 孙治国,华承俊,石岩,等.利用BRB实现桥梁排架基于保险丝理念的抗震设计 [J].振动与冲击,2015,34(22):199-205.
[13] HALLDÓRSSON B,ÓLAFSSON S,SIGBJÖRNSSON R.A fast and efficient simulation of the far-fault and near-fault earthquake ground motions associated with the June 17 and 21,2000,earthquakes in south Iceland [J].Journal of Earthquake Engineering,2007,11(3):343-370.
[14] XIE Z,ZHANG J.Design and optimization of seismic isolation and damping devices for highway bridges based on probabilistic repair cost ratio [J].Journal of Structural Engineering,2018,144(8):04018125.
[15] 张轩,温佳年,韩强,等.桥梁结构防落梁与碰撞装置综述 [J].北京工业大学学报,2021,47(4):403-420.
[16] 王东升,冯启民,王国新.基于直杆共轴碰撞理论的桥梁地震反应邻梁碰撞分析模型 [J].工程力学,2004,21(2):157-166.
[17] SILVA P F,MEGALLY S,SEIBLE F.Seismic performance of sacrificial exterior shear keys in bridge abutments [J].Earthquake Spectra,2009,25(3): 643-664.
[18] 江义,杨迪雄,李刚.近断层地震动向前方向性效应和滑冲效应对高层钢结构地震反应的影响 [J].建筑结构学报,2010,31(9):103-110.
[19] 王东升,李宏男,王国新,等.弹塑性地震反应谱的长周期特性研究 [J].地震工程与工程振动,2006,26(2):49-55.
[20] 陈力波.汶川地区公路桥梁地震易损性分析研究[ D].成都:西南交通大学,2012.
[21] 吴刚.地震作用下曲线梁桥合理约束体系研究 [D].南京:东南大学,2018.
[22] 贾毅,赵人达,王永宝,等.多跨长联连续梁桥粘滞阻尼器参数敏感性分析 [J].吉林大学学报(工学版),2019,49(6):1871-1883.