近海隔震桥梁基于性态的抗震设防标准易损性分析及应用

发布时间：2018-06-28 11:44

本文选题：近海隔震桥梁 + 基于性态的设防标准　；参考：《广州大学》2014年硕士论文

【摘要】：随着隔震技术的不断成熟和隔震装置的不断研发更新，隔震技术在建筑工程领域已经得到了广泛的应用。桥梁作为生命线工程，其抗震救灾问题越来越引起国家的高度重视；鉴于此，我国已经将隔震技术应用到桥梁工程领域，一些铁路桥梁和近海桥梁都开始采用隔震技术。大型桥梁采用隔震技术来最大限度地减轻地震灾害就必须合理的确定抗震设防标准。而目前我国近海隔震桥梁的抗震设防还无据可依，针对这一现状本文通过引入基于性态的抗震设计思想，从抗震设防标准的制定、典型桥梁易损性分析以及地震经济风险分析三方面展开一些列研究，，主要内容如下：（1）近海隔震桥梁基于性态的抗震设防标准研究：结合近海隔震桥梁的特点将桥梁分为三个设防等级，通过定义三个设防水准，将多级设防思想应用到实践中；提出“五种”性态水平，建立12个结构最低性态目标；最后提出不同等级桥梁在各级地震动作用下的抗震设计类别，为设计人员提供参考。（2）基于性态的典型桥梁地震易损性分析：基于所确定的桥梁性态标准建立一六跨连续梁桥模型，同时建立隔震桥梁非线性分析模型。对隔震支座厂家的检测数据进行统计分析得到隔震支座力学参数的变异系数；在考虑地震动不确定性、桥梁结构不确定性、支座参数不确定性基础上利用拉丁超立方抽样生成90个结构-地震动样本对；在考虑近海桥梁动水压力及波浪力的基础上，利用SAP2000有限元软件对每一个样本对进行非线性动力时程分析。以位移延性系数及支座剪应变作为破坏等级的判别指标；通过弯矩-曲率分析计算了不同破坏状态下桥墩的抗力指标，并且确定了支座不同破坏状态下的损伤指标；通过线性回归的方法分析数据最终得到桥墩、支座的易损性曲线，结果表明支座较桥墩更易损伤；利用宽限法由构件及支座的易损性数据得到桥梁系统的整体易损性曲线，结果表明采用系统整体易损性曲线的方法来判断桥梁的抗震性能更合理。（3）近海隔震桥梁地震经济风险分析：考虑不同地区危险性差异，对不同地区采用不同形状系数K，得到东南沿海地区基本烈度为8度的地震危险性曲线，进而得出相应于不同遭遇烈度的年超越概率；在基于性能工程（PEER）经济风险分析框架基础上，借助隔震桥梁地震易损性、地震危险性、经济损失比，将桥梁结构地震经济风险表达为年预期损失形式。
[Abstract]:With the development of isolation technology and the development of isolation devices, isolation technology has been widely used in the field of building engineering. As a lifeline project, bridge has attracted more and more attention from the country. In view of this, isolation technology has been applied to the field of bridge engineering in China, and some railway bridges and offshore bridges have started to use seismic isolation technology. In order to reduce earthquake disaster to the maximum extent, it is necessary to reasonably determine the standard of seismic fortification for large bridges using seismic isolation technology. However, at present, there is no basis for seismic fortification of offshore isolated bridges in our country. In view of this situation, this paper introduces the idea of aseismic design based on behavior and formulates the standard of seismic fortification. Some studies on vulnerability analysis of typical bridges and seismic economic risk analysis are carried out. The main contents are as follows: (1) study on the seismic fortification standard of offshore isolated bridge based on the behavior: combining the characteristics of offshore isolated bridge, the bridge is divided into three levels of fortification, and by defining three levels of fortification, The idea of multi-level fortification is applied to practice, and the "five" behavior level is put forward, and the minimum behavior target of 12 structures is established. Finally, the aseismic design types of bridges of different grades under the action of different levels of ground motion are put forward. It provides reference for designers. (2) Seismic vulnerability analysis of typical bridges based on behavior: based on the determined criterion of bridge behavior, the model of six span continuous beam bridge is established, and the nonlinear analysis model of isolated bridge is established at the same time. The coefficient of variation of the mechanical parameters of the isolation bearing is obtained by statistical analysis of the testing data of the isolation support manufacturer, the uncertainty of the ground motion and the uncertainty of the bridge structure are taken into account. On the basis of uncertainty of bearing parameters, 90 structure-ground motion sample pairs were generated by Latin hypercube sampling, and the dynamic pressure and wave force of offshore bridges were taken into account. The nonlinear dynamic time history analysis of each sample pair is carried out by using SAP2000 finite element software. The displacement ductility coefficient and support shear strain are taken as the criterion of failure grade, the resistance index of bridge pier under different failure state is calculated by moment curvature analysis, and the damage index of support under different failure state is determined. Through the linear regression analysis of the data, the vulnerability curve of the bridge pier and the support is obtained. The results show that the bearing is more vulnerable than the pier, and the overall vulnerability curve of the bridge system is obtained by using the vulnerability data of the component and the support. The results show that it is more reasonable to use the method of systemic vulnerability curve to judge the seismic performance of bridges. (3) the seismic economic risk analysis of offshore isolated bridges: considering the difference of risk in different regions. By using different shape coefficient K in different regions, the seismic hazard curve of 8 degrees of basic intensity in southeast coastal area is obtained, and the annual overrun probability corresponding to different encountering intensity is obtained. Based on the economic risk analysis framework of performance engineering (per), the seismic economic risk of bridge structure is expressed as the form of annual expected loss with the aid of seismic vulnerability, seismic risk and economic loss ratio of isolated bridges.
【学位授予单位】：广州大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：U442.55

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