大跨桥上纵连板式轨道受压稳定性  

Compressive Stability of Continuous-Slab-Track on Long-Span Bridge

作　　者：林红松[1] 刘学毅[1] 杨荣山[1] 

机构地区：[1]西南交通大学土木工程学院,四川成都610031

出　　处：《西南交通大学学报》2008年第5期673-678,共6页Journal of Southwest Jiaotong University

基　　金：铁道部科技研究开发计划项目(2005G015-E-2);教育部新世纪优秀人才支持计划项目(NCET-05-0798)

摘　　要：为探讨大跨桥上纵连板式轨道的受压稳定措施,根据大跨桥上纵连板式轨道的结构和纵向受力特点,以某跨径为94 m+168 m+84 m的预应力混凝土连续刚构桥为例,建立了轨道板-桥梁-墩台的有限元模型,并确定纵连板和底座板最不利段.将列车荷载作用下纵连板和底座板向上的挠曲作为初始弯曲缺陷,按照第二类稳定问题对纵连板式轨道的受压稳定性进行了分析.结果表明,对大跨桥上的纵连板式无砟轨道,在列车荷载和温度压力的共同作用下,纵连板和底座板可能发生竖向失稳,可设置"倒L"型双向挡块以增加稳定性;当纵连板和底座板的最大允许温升为30℃时,该桥"倒L"型双向挡块的间距不宜大于16.7 m.To research the compressive stability measures of continuous-slab-track on a long-span bridge, based on its structural and longitudinal mechanical features a finite element model for slab- bridge-pier was established by taking a prestressed concrete continuous rigid frame bridge with a span of 94m ＋ 168 m ＋ 84 m as an example, and the most unstable segment of continuous-slab and bed- plate was determined. By taking the upward deflection of continuous-slab and bed-plate under a train load as the initial bending defects, the nonlinear compressive stability of continuous-slab-track was analyzed. The research results show that continuous-slab and bed-plate on a long-span bridge are unstable under train and temperature loads, setting a bi-directional block like converse-L can enhance their stabilities, and the suggested distance between two adjacent bi-directional blocks should be less than 16.7 m for the example bridge when the maximum allowable temperature rising is 30℃.

关 键 词：大跨度梁桥 纵连板式轨道 稳定性分析 

分 类 号：U213[交通运输工程—道路与铁道工程]