【作者】 李超；

【导师】 王彦明； 田利； 张宇；

【作者基本信息】 山东大学 ， 土木水利（专业学位）， 2023， 硕士

【摘要】 近几十年来,国内外频繁发生特大地震,给人类社会带来了重大人员伤亡和经济损失。桥梁结构在交通系统中占有举足轻重的地位,结构的抗震性能日益受到人们的重视。随着我国现代化进程的加快,连续梁桥以其跨越能力强、受力合理、连续性好等优点被广泛应用于高速公路建设之中。高速公路连续梁桥具有多联长跨的特点,地震动空间变化效应是研究抗震性能不能忽略的因素。对此类桥梁进行空间变化地震动下的易损性分析,对评估桥梁结构的抗震水平、预测直接经济损失和指导救援运输工作均有着重要的意义。本文以京雄高速公路某多联连续梁桥为工程背景,考虑隔震与非隔震两种情况,分别对其建立了全桥非线性动力有限元模型。本文从空间变化地震的基础理论出发,模拟产生一致及多点地震时程曲线,并对桥墩与支座在一致激励及多点激励作用下的地震易损性进行研究,分析地震动空间变化效应引起桥梁结构易损性变化规律,评估了隔震前后桥梁的抗震性能及隔震效果,本文完成主要工作如下:(1)依托京雄高速某多联连续梁桥工程,建立桩土相互作用及多联效应影响下全桥非线性动态分析的有限元模型,模拟产生空间变化影响的多点地震动时程曲线,分析多联连续梁桥结构响应受行波效应,相干效应,局部场地效应等因素的影响。(2)基于地震易损性分析相关理论,建立了多联连续梁桥桥墩和支座的损伤指标与损伤等级,分析了桥梁易损部件及系统在一致激励与多点激励下的易损性,研究了桥梁在空间变化地震动下的损伤规律。(3)对于采用铅芯橡胶支座和摩擦摆隔震支座的隔震桥梁,分别建立了两种支座的损伤指标和损伤等级,开展了一致激励与多点激励下隔震多联连续梁桥桥墩和隔震支座的地震易损性分析,研究了隔震桥梁结构的抗震性能,并评估了其隔震效果。更多还原

【Abstract】 In recent decades,mega-earthquakes have occurred frequently at home and abroad,bringing significant casualties and economic losses to human society.The bridge structure occupies a pivotal position in the transportation system,and the seismic performance of the structure is getting more and more attention.With the acceleration of modernization in China,continuous girder bridges are widely used in highway construction for their strong spanning capacity,reasonable force and good continuity.High-speed continuous girder bridges are characterized by multiple long spans,and the effect of spatial variation of ground vibration is a factor that cannot be ignored in the study of seismic performance.The vulnerability analysis of such bridges under spatially varying ground shaking is of great significance in assessing the seismic level of bridge structures,predicting direct economic losses and guiding rescue and transportation work.In this paper,a multi-linked continuous girder bridge of Jingxiong Expressway is used as the engineering background,and a nonlinear dynamic finite element model is developed for the whole bridge considering both seismically isolated and nonseismically isolated cases,respectively.The paper starts from the basic theory of spatially varying earthquakes,simulates the generation of consistent and multi-point earthquake time curves,and studies the earthquake susceptibility of bridge piers and bearings under consistent excitation and multi-point excitation,analyzes the change law of bridge structure susceptibility caused by the spatially varying effect of ground shaking,and evaluates the seismic performance and seismic isolation effect of the bridge before and after seismic isolation,the main work done in this paper is as follows:(1)Based on a multi-linked continuous girder bridge project of Beijing-Xiong Expressway,a finite element model is established for the nonlinear dynamic analysis of the whole bridge under the influence of pile-soil interaction and multi-linked effect,and the multi-point ground vibration time course curve with spatial variation is simulated to analyze the structural response of the multi-linked continuous girder bridge affected by traveling wave effect,coherence effect,local site effect and other factors.(2)Based on the theory of seismic susceptibility analysis,the damage indexes and damage levels of piers and bearings of multi-linked continuous girder bridges were established,the susceptibility of bridge vulnerable components and systems under consistent and multi-point excitation were analyzed,and the damage law of bridges under spatially varying ground shaking was studied.(3)For the seismically isolated bridges with lead-core rubber bearings and friction pendulum isolated bearings,the damage indexes and damage levels of the two types of bearings were established,the seismic vulnerability analysis of the piers and isolated bearings of the seismically isolated multi-link continuous girder bridges under consistent and multi-point excitation was carried out,the seismic performance of the isolated bridge structures was studied,and the seismic isolation effects were evaluated.更多还原