摘要
结合厦门市翔安大桥装配式墩台节段预应力系统连接设计,对预应力连接系统中冷滚压螺纹预应力钢筋的力学性能开展研究。进行了75 mm直径冷滚压螺纹预应力钢筋横截面组织分析、单轴拉伸试验及疲劳性能试验研究。研究表明:75 mm直径冷滚压螺纹预应力钢筋横截面组织存在一定不均匀性,调质热处理工艺具有改进空间;冷滚压螺纹预应力钢筋的单轴拉伸应力-应变曲线无屈服平台;兼顾计算效率和计算精度,建议设计阶段结构计算模型中冷滚压螺纹预应力钢筋采用多折线模型进行计算,并且正常使用阶段,钢筋设计要求的张拉应力上限低于屈服点σ0.2;改善调质热处理参数可有效提高冷滚压螺纹预应力钢筋的疲劳性能。
Based on the connection design of the prestressed system for the prefabricated piers of Xiangan Bridge in Xiamen City,the mechanical properties of cold-rolled threaded prestressed rebars in the prestressed connection system were studied.The cross-sectional organization analysis,uniaxial tensile test,and fatigue performance test of 75 mm diameter cold-rolled threaded prestressed rebars were carried out.The results showed that there was some inhomogeneity in the cross-sectional organization of 75 mm diameter cold-rolled threaded prestressed rebars,and the heat treatment process still could be improved;the uniaxial stress-strain curve of cold-rolled threaded prestressed rebars had no yield platform;considering the efficiency and accuracy of calculation,it was suggested that the multifold model should be adopted to calculate the cold-rolled threaded prestressed rebars in the structural calculation model at the design stage.Under normal use conditions or frequently encountered loads,the design requirements for the upper limit of rebars should be lower than the yield pointσ0.2;improving the heat treatment parameters could effectively improve the fatigue performance of cold-rolled threaded prestressed rebars.
作者
林立华
傅彦青
常海林
张菁
李洁
LIN Lihua;FU Yanqing;CHANG Hailin;ZHANG Jing;LI Jie(Xiamen Road and Bridge Construction Group Co.,Ltd.,Xiamen 361000,China;Central Research Institute of Building and Construction Co.,Ltd.,MCC Group,Beijing 100088,China;Inspection and Certification Co.,Ltd.,MCC,Beijing 100088,China;School of Civil Engineering,Southwest Jiaotong University,Chengdu 610031,China)
出处
《工业建筑》
北大核心
2023年第8期199-205,共7页
Industrial Construction
关键词
装配式桥墩
预应力钢筋
大直径
冷滚压
微观组织
力学性能
prefabricated piers
prestressed rebar
large diameter
cold rolling
microstructure
mechanical properties
