摘要
为研究预制拼装桥梁UHPC湿接缝极限抗剪承载力计算方法及抗剪性能的影响因素,以台州市域铁路S2线铁路桥为背景,开展13个UHPC湿接缝模型的抗剪性能试验,得到模型接缝界面处的开裂荷载、极限抗剪承载力和界面的荷载~相对滑移关系;依据既有公式计算湿接缝极限抗剪承载力理论值,并与试验值进行比较分析,研究UHPC龄期、接缝构造形式、界面压应力等关键参数对湿接缝模型抗剪性能的影响。结果表明:基于Mohr-Coulomb准则的计算式能较准确地计算钢筋搭接平接缝模型的极限抗剪承载力理论值,其它公式欠缺对接缝粘结力的考虑;对湿接缝模型施加界面压应力可以大幅提高其开裂荷载,采用钢筋搭接可以提高所有湿接缝的抗剪性能和延性水平,UHPC龄期的增长对提高键齿接缝的抗剪性能效果显著;有界面压应力的钢筋搭接UHPC湿接缝的抗剪性能最好,更适合应用于实际工程。
This study focuses on the methods to calculate ultimate shear-carrying capacity and factors influencing the anti-shear performance of the cast-in-situ UHPC joints in prestressed segmental bridges.The railway bridges of the proposed Taizhou City Railway S2 Line are used as study cases.13 models were prepared to observe the interface cracking,ultimate shear-carrying capacity as well as the interface load-relative slip responses of the cast-in-situ UHPC joints.The theoretical and test ultimate shear-carrying capacities were compared to figure out the influence of multiple key factors on the anti-shear performance of the models with cast-in-situ UHPC joints,including the age of UHPC,joint configuration and interface compressive stress.It is shown that the equations based on the Mohr-Coulomb theory are able to accurately calculate the ultimate shear-carrying capacity of the models with lapped joints,and other equations do not consider the bond of joints.To apply interface compressive stress can significantly improve the anti-cracking strength of the models with cast-in-situ joints.Lapping can well enhance the anti-shear performance and ductility of all the joints.As the age of UHPC increases,the anti-shear performance of the keyed joints notably rises.The cast-in-situ UHPC joints applied with interface compressive stress and lapped reinforcement exhibit best anti-shear performance,and are good options for real projects.
作者
曾敏
胡方杰
于洋
田知典
朱爱珠
ZENG Min;HU Fangjie;YU Yang;TIAN Zhidian;ZHU Aizhu(China Railway Siyuan Survey and Design Group Co.,Ltd.,Wuhan 430063,China;China Railway Construction Laboratory of Bridge Engineering,Wuhan 430063,China;School of Civil and Hydraulic Engineering,Huazhong University of Science and Technology,Wuhan 430074,China)
出处
《桥梁建设》
EI
CSCD
北大核心
2023年第6期86-94,共9页
Bridge Construction
基金
中铁第四勘察设计院集团有限公司科研课题(2022K030)。
关键词
预制拼装桥梁
桥墩
湿接缝
UHPC
抗剪性能
极限抗剪承载力
参数分析
模型试验
prestressed segmental bridge
pier
cast-in-situ joint
UHPC
anti-shear performance test
ultimate shear-carrying capacity
parametric analysis
model test
