塔梁间设置BRB跨海斜拉桥减震约束体系及其地震反应  

Shock-absorbing restraint system and its seismic response of sea-crossing cable-stayed bridge installing BRB between towers and girders

作　　者：陈宝魁 王东升 李宏男 陈少林[4] 李超 CHEN Bao-kui;WANG Dong-sheng;LI Hong-nan;CHEN Shao-lin;LI Chao(School of Civil Engineering and Architecture,Nanchang University,Nanchang 330031,China;School of Civil Engineering and Transportation,Hebei University of Technology,Tianjin 300401,China;Faculty of Infrastructure Engineering,Dalian University of Technology,Dalian 116024,China;Department of Civil Engineering,Nanjing University of Aeronautics and As-tronautics,Nanjing 210016,China)

机构地区：[1]南昌大学建筑工程学院,江西南昌330031 [2]河北工业大学土木与交通学院,天津300401 [3]大连理工大学建设工程学部,辽宁大连116024 [4]南京航空航天大学土木工程系,江苏南京210016

出　　处：《振动工程学报》2021年第3期452-461,共10页Journal of Vibration Engineering

基　　金：国家自然科学基金资助项目(51868048,51778206,51808099);中国地震局工程力学研究所基本科研业务费专项资助项目(2018D18);江西省自然科学基金资助项目(20171BAB216045)。

摘　　要：提出在塔(墩)梁间设置防屈曲支撑(BRB)的斜拉桥耗能减震新型结构约束形式。以某跨海斜拉桥为工程背景,建立包括全漂浮体系、塔(墩)梁间设置黏滞阻尼器,以及塔梁间设置BRB的三类斜拉桥模型。通过比较不同约束方式斜拉桥结构在地震作用下桥塔的位移与弯矩反应,关键位置的相对位移与内力,以及耗能装置的滞回耗能响应等,确定设置BRB跨海斜拉桥新型减震约束体系的地震反应性态。研究发现斜拉桥结构设置黏滞阻尼器可以有效地减小支座以及塔(墩)梁间的相对位移,对塔顶相对于塔底的位移也有较好的控制,但明显增大了塔底及桥墩的弯矩。而设置BRB的斜拉桥结构可以大幅度降低塔(墩)底的弯矩,并且表现出了良好的耗能能力。Considering the influence of offshore ground motion and complex subsea environment on the earthquake response of seacrossing bridges,it is necessary to establish a seismic analysis model including seawater layer,seabed sites,and sea-crossing bridge.Combining finite element dynamic analysis software and wave analysis program,a novel seismic response analysis method considering pile-soil-seawater-bridge coupling is built.On this basis,A new type of energy and shock absorbing structural restraint for cable-stayed bridge is proposed.The new restraint system installs buckling-restrained braces(BRB)between the tower(pier)and the beam.A sea-crossing cable-stayed bridge is used as engineering background.According to the real site condition under seabed and the influence of seawater,three kinds of cable-stayed bridge that of full-floating system,with viscous damper between the tower(pier)and the beam,and with BRB between the tower(pier)and the beam are established.In the seismic wave analysis model for considering the pile-soil-seawater-bridge interaction,the strong earthquake records including the 3.11 earthquake in Japan are input.The displacement and bending moment response of bridge towers,the relative displacement and internal force of key positions,and the hysteretic curve of energy dissipation are compared between different restraint modes(viscous dampers and BRB).The study finds that the cable-stayed bridge with viscous dampers can effectively reduce the relative displacement of the bearing and between tower(pier)and main girder.And the displacement of tower top is also well controlled,but the bending moments of the tower(pier)bottoms are significantly increased.However,the cable-stayed bridge structure setting the BRB can greatly reduce the bending moment of the bottom of towers(piers),and have a good energy consumption.

关 键 词：斜拉桥 防屈曲支撑 减震耗能 地震反应分析 海底地震动 

分 类 号：U448.27[建筑科学—桥梁与隧道工程] U441.3[交通运输工程—道路与铁道工程]