冻融循环与持续荷载共同作用下FRP片材-混凝土界面黏结性能的退化行为  

Bond performance degradation behavior of FRP laminate-to-concrete interface under combined effects of freeze-thaw cycling and sustained loading

作　　者：陈雨唐 缪凡璠 唐晨 刘钰汶 施嘉伟 CHEN Yutang;MIAO Fanfan;TANG Chen;LIU Yuwen;SHI Jiawei(College of Civil and Transportation Engineering,Hohai University,Nanjing 210098,China)

机构地区：[1]河海大学土木与交通学院

出　　处：《河海大学学报（自然科学版）》2019年第5期468-476,共9页Journal of Hohai University(Natural Sciences)

基　　金：国家自然科学基金(51508157);河海大学创新训练项目(2017102941087)

摘　　要：为研究冻融循环影响下纤维增强复合材料(FRP)外贴加固混凝土结构的界面性能,通过双面剪切试验研究冻融循环与持续荷载共同作用下FRP片材-混凝土界面黏结性能的退化行为。在经历最大200次冻融循环作用后,对试件进行静态加载,并采用数字图像相关法量测试件表面的全场位移,进而计算界面黏结滑移关系。试验结果表明:冻融循环作用对FRP片材-混凝土界面的极限承载力、极限滑移、FRP最大应变、最大剪应力、界面断裂能等均有明显的削弱作用,界面黏结滑移曲线退化显著;预加荷载的存在加剧了冻融循环作用后界面黏结性能的退化;冻融循环作用前后界面的破坏模式也发生了显著改变。To study interfacial behavior of concrete structures strengthened with fiber reinforced polymer(FRP)subjected to the freeze-thaw cycling,this study presents experimental investigations on the degradation behavior of FRP laminate-to-concrete interfacial bond performance under combined effects of freeze-thaw cycling and sustained loading with double-lap shear tests.After being exposed up to 200 freeze-thaw cycles,the specimens were tested to failure monotonously.Digital image correlation method was employed to capture the full-field displacement of the specimen during loading.Interfacial bond stress-slip relationship was determined based on the analysis of full-field data.Test parameters included the freeze-thaw cycles,sustained loading and concrete types.Test results show that the freeze-thaw cycling leads to significant decreases in all interfacial parameters.The bond stress-slip relationship is also degenerated with freeze-thaw cycles seriously.When considering the sustained loading,additional interfacial degradations were observed after freeze-thaw cycling.Apparent changes of interfacial failure modes were also observed during tests.

关 键 词：FRP 混凝土 界面 冻融循环 持续荷载 

分 类 号：TU375.2[建筑科学—结构工程]