预应力钢丝绳加固空心混凝土桥墩试验研究  

Experim entalStudy on Strengthening Hollow Concrete Bridge Piers With Prestressed Wire Ropes

作　　者：宋军[1] 雷欢 黄彬 孙敦华 朱俊[4] Song Jun;Lei Huan;Huang Bin;Sun Dunhua;Zhu Jun(Tongji University,Shanghai 200092,China;Liuzhou OVM Machinery Co.,Ltd.,Liuzhou 545005,China;Anhui Transportation Holding Group Co.,Ltd.,Hefei 230092,China;Anhui Transport Consulting&Design Institute Co.,Ltd.,Hefei 230092,China)

机构地区：[1]同济大学,上海200092 [2]柳州欧维姆机械股份有限公司,广西柳州545005 [3]安徽省交通控股集团有限公司,安徽合肥230092 [4]安徽省交通规划设计研究总院股份有限公司,安徽合肥230092

出　　处：《市政技术》2024年第11期156-163,共8页Journal of Municipal Technology

基　　金：安徽省交通控股集团科技项目(JKKJ-2020-41)。

摘　　要：为加固桥墩竖向裂缝、抑制裂缝的发展和新裂缝的产生,开展了4组环形预应力钢丝绳加固空心混凝土桥墩试验,研究了钢丝绳拉力、混凝土径向压力、混凝土表面环向压应变的分布规律。试验结果表明:由于钢丝绳与混凝土桥墩表面摩阻力产生的预应力损失,钢丝绳拉力与对应的混凝土径向压力在张拉端最大,随着远离张拉端逐渐减小;混凝土表面环向压应变沿圆周随着远离张拉端逐渐减小,沿竖向随着远离钢丝绳逐渐减小。根据试验结果计算出摩擦系数为0.18,对应的最大预应力损失为43%。建立了相应的有限元模型,有限元计算结果与试验结果吻合良好。设定当混凝土表面环向压应变大于50×10^(-6)时为有效加固区域,结果表明在多根钢丝绳组合布置下,可建立范围较大的有效加固区域,验证了预应力钢丝绳的加固效果。In order to reinforce the vertical cracks in bridge piers,suppress crack propagation,and prevent the new cracks,four experiments of strengthening hollow concrete bridge piers were conducted by circular prestressed wireropes to investigate the distribution law of the wire-ropes tension,the concrete radial pressure,and the circumferential strain on the concrete surface.The experimental results indicate that the tension in the wire ropes and the corresponding concrete radial pressure are the maximum at the tensioning end and gradually decrease as they move away from the tensioning end due to the pre-tension loss caused by the frictional resistance between the wire-ropes and the concrete pier surface;The circumferential strain on the concrete surface decreases along the circumference as it moves away from the tensioning end and decreases vertically as it moves away from the wire-ropes.Based on the experimental results,a friction coefficient of 0.18 and a corresponding maximum pre-tension loss of 43%were calculated.A corresponding finite element model was established.The finite element calculation results aligned well with the experimental results.An effective reinforcement region,where the circumferential strain exceeding 50×10^(-6),is defined.Under the arrangement of multiple wire-ropes,a relatively large effective reinforcement area can be established,thus the reinforcement efficacy of prestressed wire-ropes will be verified.

关 键 词：裂缝 加固 环形预应力 钢丝绳 空心桥墩 环向压应变 

分 类 号：U445.72[建筑科学—桥梁与隧道工程]