铁路混凝土箱梁是否设置横向预应力筋的探讨  

Discussion on Whether to Set Transverse Prestressed Reinforcement in Railway Concrete Box Girder

作　　者：鲁雪冬[1] 宋晓东[1] LU Xuedong;SONG Xiaodong(China Railway Eryuan Engineering Group Co.Ltd.,Chengdu 610031,China)

机构地区：[1]中铁二院工程集团有限责任公司,成都610031

出　　处：《铁道建筑》2022年第1期78-82,共5页Railway Engineering

摘　　要：针对铁路混凝土箱梁顶板是否设置横向预应力筋作法不统一的问题,从结构受力、经济性、施工工艺及结构耐久性方面分析了箱梁顶板设置横向预应力筋的效用及影响。研究结果表明:铁路预应力混凝土箱梁顶板不设置横向预应力筋,只采用普通钢筋配置方式,结构受力和裂缝宽度依然能满足规范要求;顶板如不设置横向预应力筋,施工时则不用预埋相应管道,省去了预应力的张拉和施工后的封锚工序,不仅施工程序得以简化,混凝土可以一次浇筑成型,还能够有效保证混凝土密实性和施工质量,亦避免了封锚处防水处理不好引起锚头锈蚀的风险,提高结构耐久性,减少工程量,降低造价。In view of the inconsistency of whether the transverse prestressed reinforcement should be set on the top flange of railway concrete box girder,the effect and influence of setting transverse prestressed reinforcement on the top flange of box girder was studied from the aspects of structural stress,economy,construction technology and durability.The research results show that if the transverse prestressed reinforcement is not set on the top flange of box girder while only the ordinary reinforcement configuration is set,the structural stress and crack width can meet the specification requirements.If the transverse prestressed reinforcement is not set on the top flange,the corresponding pipeline embedment during construction is not required,eliminating the tensioning of prestressed reinforcement and anchor sealing after construction.Not only the construction procedure can be simplified,the concrete can be poured and formed at one time,but also the concrete compactness and construction quality can be effectively ensur.This can avoid the risk of anchor head corrosion caused by poor waterproof treatment at the anchor sealing place,improve the structural durability,and reduce the engineering quantity and save the cost.

关 键 词：铁路桥梁 混凝土箱梁 简支梁 连续梁 横向预应力筋 箱梁顶板 

分 类 号：U448.213[建筑科学—桥梁与隧道工程] TU378.2[交通运输工程—道路与铁道工程]