【作者】 李焱；

【导师】 李晓莉；

【作者基本信息】 大连海事大学 ， 交通运输硕士（专业学位）， 2024， 硕士

【摘要】 近年来,地震灾害频繁发生在世界各地,桥梁作为生命线工程,承担了抗震救灾以及灾后重建的工作。如果桥梁在强烈地震中受损,将导致更严重的后果。近年来,下承式钢管混凝土系杆拱桥因具有对地基要求不高,力学性能优越等特点,故在数量上不断增多。我国在世界上所处的地理位置导致国内含有近断层区域,在我国桥梁工程建设初期,桥梁工程的覆盖密度不大,可以考虑避开近断层区域进行桥梁工程的选址,但随着我国桥梁发展程度不断上升,已建和在建桥梁的数量逐年增加,不可避免地需要开展近断层区域桥梁建设的工程。近断层地震动会导致桥梁产生严重破坏甚至引起坍塌,研究桥梁在近断层区的稳定性具有一定工程意义。本文针对近断层地震动作用下的下承式钢管混凝土系杆拱桥的抗震性能进行研究,提出减震措施研究其对此类桥梁抗震性能的影响。本文的主要研究内容如下:(1)建立百崎湖大桥有限元模型,将动力特性分析结果与既有文献比较,验证本文建立模型的正确性。对百崎湖大桥进行反应谱分析,研究桥梁在E1地震作用下的地震响应特征,并验证所筛选地震波的合理性。(2)使用筛选的7条近断层脉冲型地震动和7条近断层非脉冲型地震动,研究近断层地震动特性对桥梁结构地震响应的影响。研究构件包含桥梁结构上部结构中的拱圈、系杆、吊杆和横撑和下部结构的墩部。从近断层地震动输入模式、近断层脉冲效应和近断层竖向地震动三个角度出发,探讨近断层地震动各项特征对下承式钢管混凝土系杆拱桥的影响规律。(3)使用摩擦摆支座作为减震支座,将原始桥梁体系改为含摩擦摆支座的减震体系,对桥梁进行减震分析。对比关键部位在设置摩擦摆支座前后的地震响应,研究摩擦摆支座对桥梁结构地震响应的影响。建立不同支座半径和动摩擦系数的研究工况,对比不同参数下的桥梁地震响应变化。(4)使用粘滞阻尼器作为减震构件,对桥梁结构进行减震分析。对比关键部位在设置粘滞阻尼器前后的地震响应,研究粘滞阻尼器对桥梁结构地震响应的影响。建立不同阻尼系数和阻尼指数下的研究工况,研究地震响应对粘滞阻尼器参数的敏感性。更多还原

【Abstract】 In recent years,earthquake disasters have occurred frequently all over the world.Bridges,as lifeline projects,have taken on the work of earthquake relief as well as post-disaster reconstruction.If the bridge is damaged in a strong earthquake,it will lead to more serious consequences.In recent years,the number of through concrete-filled steel tubular tied arch bridges has been increasing because of their low requirements on the foundation and superior mechanical properties.The geographical location in the world leads to the existence of nearfault areas in China.In the early stage of bridge engineering construction in our country,the coverage density of bridge engineering is not large,and the location of bridge engineering can be considered to avoid the near-fault areas.However,with the continuous development of bridges in our country,the number of bridges built and under construction is increasing year by year,and it is inevitable to carry out bridge construction projects in near-fault areas.Near-fault ground motion can cause serious damage to the bridge and even cause collapse.It is of great engineering significance to study the stability of the bridge in the near-fault area.In this thesis,the seismic performance of through concrete-filled steel tubular tied arch bridge under nearfault ground motion is studied,and the damping measures are proposed to study its influence on the seismic performance of such bridges.The main research contents of this thesis are as follows :(1)The finite element model of Baiqi Lake Bridge is established,and the dynamic characteristics analysis results are compared with the existing literature to verify the correctness of the model established in this paper.The response spectrum analysis of Baiqi Lake Bridge was carried out to study the seismic response characteristics of the bridge under the action of E1 earthquake,and the rationality of the selected seismic waves was verified.(2)Seven near-fault pulse-type ground motions and seven near-fault non-pulse-type ground motions were selected to study the influence of near-fault ground motion characteristics on the seismic response of bridge structures.The research components include the arch ring,tie rod,suspender and transverse brace in the upper structure of the bridge structure and the pier of the lower structure.From the three perspectives of near-fault ground motion input mode,near-fault pulse effect and near-fault vertical ground motion,the influence of various characteristics of near-fault ground motion on the through concrete-filled steel tube tied arch bridge is discussed.(3)The friction pendulum bearing is used as the shock absorption bearing,and the original bridge system is changed to the shock absorption system with friction pendulum bearing,and the shock absorption analysis of the bridge is carried out.The influence of friction pendulum bearing on the seismic response of bridge structure is studied by comparing the seismic response of key parts before and after setting friction pendulum bearing.The research conditions of different bearing radius and dynamic friction coefficient are established,and the seismic response changes of the bridge under different parameters are compared.(4)The viscous damper is used as the damping component to analyze the damping of the bridge structure.The influence of viscous damper on the seismic response of bridge structure is studied by comparing the seismic response of key parts before and after setting viscous damper.The research conditions under different damping coefficients and damping indexes are established to study the sensitivity of seismic response to viscous damper parameters.更多还原