摘要
地震作用下结构破坏模式研究是合理保证结构震后安全性的基础,而目前对大跨度悬索桥破坏模式的研究还很少。在大跨度悬索桥中,主缆、加劲梁、吊索等构件组成柔性悬吊体系一般采用钢结构,而主塔为核心支撑构件,且目前在我国修建的大跨度悬索桥中,基本都是门式或框架式的钢筋混凝土桥塔。因此,地震破坏模式的研究重点为大跨度悬索桥的钢筋混凝土桥塔。借助大型有限元分析程序,以润扬大跨度悬索桥的设计方案为背景,对地震作用下大跨度悬索桥纵向破坏模式及其特征展开探讨,发现其桥塔地震破坏模式为具有同时性特征的双塑性铰破坏模式,此失效模式表明此时塑性铰依次形成机制不存在,其屈服后的塑性性能是否能如中小桥梁一样被大幅利用以及如何利用,应由桥塔的塑性动力稳定决定。
Research on structural failure patterns forms the basis for structures to survive serious earthquakes.However,study of the failure patterns of long span suspension bridges under earthquake is rarely seen in the literature.For long span suspension bridges in China,the suspension part,consisting of main cables,stiffening girds and hanger ropes,is usually made of steel,and the pylon towers,as the core structural support components,are usually composed of reinforced concrete frames.Therefore,the focus of the study on the failure patterns of long span suspension bridges is on the reinforced concrete pylon towers.The longitudinal failure pattern and corresponding characteristics of long span suspension bridges under earthquake are investigated through finite element analysis with the Runyang long span suspension bridge as the example.The failure pattern is found to be in the form of synchronal double plastic-hinges.This implies that such mechanism in which the plastic hinges generate successively does not exist.Hence,whether or not the stiffness,after yielding of the pylon towers,can be used just like short or middle span reinforced concrete bridge depends on the structure＇s plastic buckling behavior under earthquake.
出处
《土木工程学报》
EI
CSCD
北大核心
2011年第4期91-97,共7页
China Civil Engineering Journal
基金
国家自然科学基金(505090060)
江苏省自然科学基金(BK2005110)
江苏省"青蓝工程"项目资助
关键词
地震作用
大跨度悬索桥
破坏模式
具有同时性的双塑性铰
塑性动力稳定
earthquake
long span suspension bridge
failure pattern
synchronal double plastic-hinges
plastic buckling stability
