铁路矮塔斜拉桥索梁锚固区局部应力分析  

Analysis of Local Stress on Cable-Girder Anchorage Zone for the Extradosed Cable-Stayed Bridge in Railway

作　　者：毛晓东 MAO Xiao-dong(Gansu Luqiao Highway Investment Co.,Ltd,Lanzhou 730070,China)

机构地区：[1]甘肃路桥公路投资有限公司,甘肃兰州730070

出　　处：《兰州交通大学学报》2018年第2期1-6,共6页Journal of Lanzhou Jiaotong University

摘　　要：为了分析铁路矮塔斜拉桥索梁锚固区在索力作用下的应力分布,以新建的某铁路矮塔斜拉桥为工程背景,采用实体单元和梁单元建立了索梁锚固区的整体有限元模型,对索梁锚固区在最不利荷载组合作用下的受力性能进行了研究,提出的实体单元和梁单元组合使用的整体有限元模型可将矮塔斜拉桥索梁锚固区的边界问题处理的更加合理准确,丰富了索梁锚固区空间应力的分析方法.结果表明:1)索梁锚固区的锚块在靠近纵梁处有应力集中现象,设计中应注意增加分布钢筋和表面抗裂钢筋网片,以提高结构抗裂性;2)成桥阶段的索梁锚固区整体处于较合理的受压状态,说明该结构截面尺寸设计合理;3)研究方法可为铁路用矮塔斜拉桥的索梁锚固区的局部应力分析提供参考.To know the stress distribution of cable-girder anchorage zone under cable forces for the extradosed cable-stayed bridge in railway,taking a newly built railway extradosed cable-stayed bridge as an example,using solid element and beam element,the whole finite element model of cable girder anchorage structure was established and the the mechanical behaviour of cable girder anchorage zone under the most unfavorable load combination was studied.The whole finite element model established by using solid element and beam element can be adopted to deal with the boundary problems of the cable girder anchorage zone more reasonably and accurately,which enriches the stress analysis method for the anchorage zone.Research conclusions are that 1)There is stress concentration in the anchor block of cable girder anchorage zone near the longitudinal girder,so attention should be paid to increasing the reinforcement distribution of rebar and surface anti crack mesh in order to improve crack resistance of structure.2)In the stage of completion of the bridge,the cable girder anchorage zone is in a more reasonable compression condition,which shows that the structure design is reasonable.3)The research method in this paper can provide reference for the local stress analysis of the cable girder anchorage zone of the extradosed cable-stayed bridge for railway.

关 键 词：矮塔斜拉桥 索梁锚固 有限元分析 应力分布 应力集中 

分 类 号：U24[交通运输工程—道路与铁道工程]