考虑钢筋腐蚀的近海隔震桥梁地震易损性分析  

Vulnerability analysis of offshore isolation bridges considering reinforcement corrosion

作　　者：柳春光[1] 任文静[1] 夏春旭 

机构地区：[1]大连理工大学建设工程学部水利工程学院,辽宁大连116024

出　　处：《自然灾害学报》2016年第6期120-129,共10页Journal of Natural Disasters

基　　金：国家自然科学基金项目(51678107);国家重点基础研究发展计划资助"973计划"项目(2011CB013605)~~

摘　　要：基于氯离子腐蚀作用模型,对混凝土中钢筋锈蚀机理及过程开展了研究,进而建立了钢筋直径及屈服强度的退化模型。为了研究氯离子侵蚀对隔震桥梁抗震性能的影响,选取我国某一长期处于海洋潮汐环境中受氯离子腐蚀影响显著的近海隔震桥梁为算例,基于Open Sees平台分别建立了不考虑和考虑钢筋腐蚀的全桥有限元模型,然后选取15条合适的地震波进行了IDA分析,并根据构件需求能力比建立了板式橡胶支座和桥墩在不同破坏状态下的易损性曲线,最终基于概率论知识完成了全桥的系统易损性曲线。计算结果表明:对于隔震桥梁而言,板式橡胶支座比桥墩更容易发生破坏;全桥系统比任何单一构件都更容易发生破坏,采用全桥易损性曲线评价桥梁的抗震性能更加合理;考虑钢筋腐蚀后,全桥地震易损性增强,说明在氯离子侵蚀环境下,钢筋的腐蚀问题不可忽略。The steel reinforcement corrosion mechanism and process in concrete was researched considering the chlorion corrosion effect model. Then the degradation model of the diameter and yield strength of the reinforcement was established. In order to study the degeneration law of seismic performance of isolation bridges caused by chlori- on corrosion, an offshore isolation bridge exposed to long-term corrosion of chlorion in China was taken as an exam- ple, and then finite element model of bridges was established with and without considering the chlorion corrosion effect by use of OpenSees program. Moreover, 15 appropriate seismic waves were selected to conduct IDA analy- ses. The vulnerability curves of piers and plate-type rubber bearings under different damage states were established according to the ratios of the capacity and demand. Finally, the systematic vulnerability curves of whole bridge were formed based on knowledge of probabilistic theory. Calculations show that plate-type rubber bearing is more vulnera- ble than pier for isolation bridge. Meanwhile, whole bridge system is more vulnerable than any single component and it is more reasonable to assess the seismic behavior of bridge with systematic vulnerability curve of whole bridge. The seismic vulnerability of the bridge system is increased after considering the reinforcement corrosion, which illustrates that the reinforcement corrosion could not be ignored in the environment of chlorion erosion.

关 键 词：隔震桥梁 氯离子侵蚀作用 钢筋腐蚀 IDA分析 易损性分析 

分 类 号：P315.7[天文地球—地震学]