等幅疲劳加载后锈蚀钢筋静力本构关系研究  

Study on static constitutive relation of corroded steel bars after constant amplitude fatigue loading

作　　者：欧阳祥森[1,2] 罗小勇[1] 邹洪波[2] 肖烨 OUYANG Xiangsen;LUO Xiaoyong;ZOU Hongbo;XIAO Ye(School of Civil Engineering,Central South University,Changsha 410075,China;College of Architecture Engineering,Hunan Institute of Engineering,Xiangtan 411104,China)

机构地区：[1]中南大学土木工程学院,湖南长沙410075 [2]湖南工程学院建筑工程学院,湖南湘潭411104

出　　处：《铁道科学与工程学报》2020年第4期972-979,共8页Journal of Railway Science and Engineering

基　　金：国家自然科学基金资助项目(U1361204);湖南省教育厅优秀青年项目(19B124)。

摘　　要：锈蚀钢筋在承受疲劳荷载作用后,其应力-应变关系相较于静力荷载作用下的应力-应变关系出现了明显的区别。为探讨准确的锈蚀钢筋疲劳加载后应力-应变关系,开展不同锈蚀率钢筋的静力拉伸试验和疲劳加载后静力拉伸试验。试验结果表明:锈蚀钢筋静力拉伸断裂,断面不规则,有颈缩现象,屈服平台随锈蚀率的增加而缩短直至完全融入强化段。锈蚀钢筋承受疲劳荷载后会产生残余变形,残余变形按较快增长、稳定增长、快速增长3阶段规律发展。依据试验数据拟合锈蚀钢筋疲劳残余应变演化方程,定义以残余应变表述的锈蚀钢筋损伤变量。建立疲劳荷载作用后锈蚀钢筋静力拉伸本构关系模型,成果可为锈损结构耐久性、剩余承载力、疲劳性能评估提供试验参考。The stress-strain relationship of corroded steel bars under fatigue load is obviously different from that under static load.In order to investigate the accurate stress-strain relationship of corroded steel bars after fatigue loading,static tensile test of steel bars with different corrosion rates and static tensile testof steel bars with different corrosion rates after fatigue loading were carried out.The result indicated that the rusted steel bars are statically tensile fractured,the cross section is irregular,and there is a necking phenomenon.The yielding platform is shortened with the increase of the corrosion rate until it is fully integrated into the strengthening section.Corroded steel bars will produce residual deformation after fatigue load,and the development of residual deformation meets the three-stage development law of rapid growth,steady growth and rapid growth According to the experimental data fitting,the fatigue residual strain evolution equation of corroded steel bars is established,and the damage variable of corroded steel bars expressed by residual strain is defined.The stress-strain constitutive model of corroded steel bars after fatigue loading is established.The results can provide experimental reference for the durability,residual load bearing capacity and fatigue performance of corroded structures.

关 键 词：桥梁工程 钢筋锈蚀 疲劳荷载 疲劳残余应变 应力-应变关系 

分 类 号：U441[建筑科学—桥梁与隧道工程] TU528.57[交通运输工程—道路与铁道工程]