预应力连接预制节段桥墩抗震性能数值仿真分析  

Numerical Analyses on Seismic Performance of Precast Segmental Prestressed Bridge Columns

作　　者：张凯迪 贾俊峰[1,2] 郭彤 程寿山[2] 樊平 ZHANG Kaidi;JIA Junfeng;GUO Tong;CHENG Shoushan;FAN Ping(Key Lab.of Urban Security and Disaster Eng.of Ministry of Education,Beijing Univ.of Technol.,Beijing 100124,China;Key Lab.of Transport Industry of Bridge Detection Reinforcement Technol.(Beijing),Beijing 100088,China;Key Lab.of Concrete and Prestressed Concrete Structures of Ministry of Education,Southeast Univ.,Nanjing 210096,China)

机构地区：[1]北京工业大学城市与工程安全减灾教育部重点实验室,北京100124 [2]旧桥检测与加固技术交通行业重点实验室(北京),北京100088 [3]东南大学混凝土及预应力混凝土结构教育部重点实验室,江苏南京210096

出　　处：《工程科学与技术》2022年第6期176-184,共9页Advanced Engineering Sciences

基　　金：国家重点研发计划政府间国际科技创新合作重点专项(2019YFE0119800);国家自然科学基金项目(51778024;52178449);北京市自然科学基金项目(8202002);旧桥检测与加固技术交通行业重点实验室(北京)开放课题(2020-JQKFKT-7)。

摘　　要：预应力连接预制节段桥墩已在美国低震地区广泛应用,但在中国的工程应用甚少。由于预制节段墩的抗震机理尚不明确,震害资料缺乏,使其在强震地区的应用受到制约。本文基于预应力连接预制节段桥墩缩尺模型的拟静力试验,采用有限元分析软件ABAQUS,建立其精细化数值模型,在压弯荷载作用下进行墩柱的非线性力学行为仿真,并与试验结果进行对比验证;在此基础上,探讨耗能钢筋配筋率、预应力筋面积及其初始张拉力3个关键设计参数对预制节段桥墩抗震性能的影响规律。结果表明:本文建立的预制节段桥墩数值模型可较好地再现拟静力试验结果;随耗能钢筋配筋率的增加,桥墩承载能力、等效黏滞阻尼比和残余位移都明显增加;随预应力筋面积增加,桥墩屈服后刚度明显增加,抗侧承载力增加,残余位移略有增加,等效黏滞阻尼比降低;随预应力筋初始张拉力的增加,桥墩承载能力增加,但墩底混凝土破碎严重;对于预制节段拼装预应力桥墩,建议当目标偏移率不超过4%时,为了避免严重的混凝土损伤,预应力筋初始张拉力应小于其极限抗拉强度的50%;为了实现桥墩震后的快速修复,耗能钢筋配筋率应小于1%。研究结果可为预制节段拼装预应力桥墩的抗震设计提供参考,促进其在强震地区的使用。Precast segmental prestressed bridge columns have been widely applied in the region of medium and low seismicity in the United States,however,there are few applications in China.Due to the lack of seismic damage data and insufficient knowledge of their seismic performance,their application in high seismicity is limited.According to the existing quasi-static test of precast segmental prestressed bridge columns,the numerical model of the precast column under bending load was developed by software ABAQUS and the nonlinear behavior was verified by experimental results.Based on the verified numerical model,influences of three parameters,namely reinforcement ratio of energy dissipation(ED)bars,area of prestressed tendons and initial prestressing level on seismic performance of precast segmental columns were investigated.The results show that the results of the model are in good agreement with the experimental results.With the increase in the reinforcement ratio of ED bars,the energy dissipation capacity bearing capacity,and residual displacement increase severely.As the area of the prestressed tendon increases,the bearing capacity and post-yield stiffness increase significantly,whereas the energy dissipation capacity decreases.With the increase of the initial prestressing level, the bearing capacity of the column increases, but the damage at the bottom of the precast columns is more severe. There-fore, when the target displacement drift is less than 4%, the initial prestressing level should be less than 50% of the ultimate tensile strength of prestressed tendons to avoid serious concrete damage, and the reinforcement ratio of ED bars should be less than 1% to achieve quick repair of columns after an earthquake. The research results could provide technical support for the seismic design of precast segmental prestressed bridge columns and their application in strong earthquake areas.

关 键 词：预制节段预应力桥墩 抗震性能 耗能钢筋配筋率 预应力筋面积 预应力筋初始张拉力 

分 类 号：TU375[建筑科学—结构工程]