地震作用下中小跨度梁桥横向碰撞参数影响分析  

Parametric analysis of transverse collison of medium and small-span bridges under earthquake excitaiton

作　　者：焦驰宇[1] 龙佩恒[1] 李士锣 候苏伟 刘陆宇[1] 

机构地区：[1]北京建筑大学土木与交通工程学院,北京100044 [2]贵港新兴城投有限责任公司,广西贵港537100

出　　处：《振动与冲击》2014年第8期48-53,77,共7页Journal of Vibration and Shock

基　　金：建设部研究开发项目"多联超长城市高架桥地震反应特点与合理抗震体系研究"(2010-k3-47);北京市优秀人才项目"北京市已建城市桥梁地震易损部位及合理加固措施研究"(070900601);北京市教委科技计划面上项目(2013)"考虑土-桥台-结构相互作用的曲线桥地震破坏机理研究"(KM201310016007);国家青年自然科学基金"基于精细化数值模拟的FPS隔震曲线桥抗震性能研究"(51308027)

摘　　要：地震作用下挡块与主梁的横向碰撞是影响桥梁结构地震响应的重要因素,目前缺乏针对城市高架桥中广泛使用的双柱式小箱梁结构横向碰撞问题的研究。以此类桥梁的典型工程为代表,建立了空间有限元模型,利用Kelvin模型对横向碰撞进行了准确模拟,重点探讨了接触单元刚度、挡块-主梁间隙、桥墩墩高、场地类别、上部结构与盖梁质量比等关键因素对双柱式小箱梁结构桥梁地震响应的影响。研究结果表明:碰撞刚度、碰撞间隙对双柱墩墩底内力有较大影响,应尽可能通过试验予以确定;场地特性、上部结构和盖梁质量比、桥墩高度等设计参数,均会对桥梁的地震受力产生较大影响,因而应在设计选型时进行适当的调整,并尽可能选择坚硬场地下高墩轻质主梁结构体系,研究成果可为同类高架桥的设计提供技术支持。Transverse collisions between restrain blocks and main girders under earthquake are the important factors affecting the seismic response of a bridge.Recent researches lack dicussions of the lateral collision problems related to double-column and box-girder bridges（DCBGBs）widely used in urban viaducts.Taking such a bridge as an example,a spatial finite element model was built,the lateral collision was accurately simulated with Kelvin-model.Then the effects of the key factors,such as,impact stiffness,restrain block-main girder gap,height of bridge pier,site category,mass ratio of upper structure to cap beam on the seismic responses of the bridge were analyzed.The results showed that the impact stiffness and impact clearance have a greater influence on the internal forces of the double column pier bottom,they should be determined with testes as correctly as possible;the design parameters,such as,site features,mass ratio of super structure to cap beam and pier height also have a great influence on the bridge forces,therefore they should be carefully adjusted when the bridge is designed;choosing a harder site,higher piers and lightweight main girders for a bridge is a good idea.The study results provided a technical support for design of similar viaducts.

关 键 词：地震反应 双柱式梁桥 横向碰撞 参数分析 

分 类 号：U442.59[建筑科学—桥梁与隧道工程]