预制拼装桥梁UHPC横向连接技术研究  

Research on UHPC Transverse Connection Technology of Precast & Assembled Bridges

作　　者：曹全付 秦凤江[2] 姜瑞娟 罗新才 尹光亮 崔燕 CAO Quan-fu;QIN Feng-jiang;JIANG Rui-juan;LUO Xin-cai;YIN Guang-liang;CUI Yan(Guangdong Nanyue Transportation Investment Construction Co.,Ltd.,Guangzhou 510623,China;College of Civil Engineering,Chongqing University,Chongqing 400044,China;Shenzhen Municipal Design&Research Institute Co.,Ltd.,Shenzhen 518029,China)

机构地区：[1]广东省南粤交通投资建设有限公司,广东广州510623 [2]重庆大学土木工程学院,重庆400044 [3]深圳市市政设计研究院有限公司,广东深圳518029

出　　处：《中国市政工程》2024年第4期16-21,31,149,共8页China Municipal Engineering

基　　金：国家自然科学基金面上项目(51878391);“十四五”国家重点研发计划项目(2021YFF0501000)。

摘　　要：以广东省湛江市湛江环城高速南三岛大桥工程为依托,设计并开展了5组基于不同钢筋搭接形式和搭接长度的普通混凝土预制小箱梁横向湿接缝纯弯试验,给出了适用于该项目的超高性能混凝土(UHPC)横向湿接缝构造方案。试验结果表明:钢筋搭接长度和搭接形式对桥面板开裂荷载影响小;搭接长度不小于6倍钢筋直径时,可为直径16 mm的U形钢筋在UHPC横向湿接缝中提供足够的锚固能力,此时湿接缝内纵向钢筋屈服后应变得到充分发展,试件破坏模式为纯弯段普通混凝土压碎的延性破坏,试件强度和延性满足实际工程需求;而湿接缝内横向钢筋的应变小于350με,其布设对提高试件承载力的作用有限。此外,基于UHPC的横向湿接缝大幅缩短了钢筋搭接长度和湿接缝宽度,有助于提升桥梁的受力性能和耐久性。Based on the Nansandao Bridge project of Zhanjiang Ring Expressway,five groups of pure bending tests of transverse wet joints of ordinary concrete precast small box girders based on different reinforcement overlapping forms and lengths are designed and carried out,and the construction scheme of ultra-high performance concrete(UHPC) transverse wet joints suitable for the project is given.The test results show that the lap length and lap form of reinforcement have little effect on the cracking load of bridge deck;when the lap length is not less than 6 times the diameter of the reinforcement,the U-shaped reinforcement with a diameter of 16 mm can provide sufficient anchorage capacity in the UHPC transverse wet joint.At this time,the strain of the longitudinal reinforcement in the wet joint is fully developed after yielding.The failure mode of the specimen is the ductile failure of the crushing of the ordinary concrete in the pure bending section,and the strength and ductility of the specimen meet the actual engineering needs;the strain of transverse reinforcement in the wet joint is less than 350 με,which has limited effect on improving the bearing capacity of the specimen.In addition,the transverse wet joint based on UHPC significantly shortens the lap length and wet joint width of reinforcement,which helps to improve the mechanical performance and durability of the bridge.

关 键 词：预制拼装桥梁 超高性能混凝土 横向湿接缝 连接性能 

分 类 号：U448.35[建筑科学—桥梁与隧道工程]