高温对CFRP板/钢界面力学性能的影响  

Effect of high temperature on mechanical properties of the interface between CFRP laminate and steel

作　　者：李传习[1] 罗南海 LI Chuan-xi;LUO Nan-hai(Key Laboratory of Bridge Engineering Safety Control by the Ministry of Education in China,Changsha University of Science&Technology,Changsha 410114,China)

机构地区：[1]长沙理工大学桥梁工程安全控制教育部重点实验室

出　　处：《交通科学与工程》2019年第4期34-39,共6页Journal of Transport Science and Engineering

基　　金：国家自然科学基金资助项目(51778069,51708047);广东省交通厅科技项目(201602010);国家建设高水平大学公派研究生项目(201808430209);科技部973项目(2015CB057701)

摘　　要：针对结构加固常用胶粘剂耐高温性能差的现象,采用一种新型高强度胶粘剂(环氧载体胶膜),运用动态热机械分析法,获得了该胶膜的动态力学性能温度谱。制作了9个CFRP板/钢双搭接接头试件,分别在3种不同环境温度下进行了拉伸实验,并对试件的破坏模式、承载力及传力规律等进行了研究。研究结果表明:该胶膜基于储能模量的玻璃转化温度为69.5℃,远大于常用胶粘剂的玻璃转化温度;试件的极限承载力随着温度的升高而降低,70℃时试件的极限承载力相对于40℃时的只下降了8.4%,表明该胶膜的耐高温性能良好;温度越高,试件的有效粘结长度越长。实际工程加固时,应根据环境温度选择合适的碳纤维增强复合材料粘结长度;加载过程中,峰值剪应力逐渐向接头CFRP板端移动,在同等荷载(如:150 kN)作用下,温度越高,试件界面的剥离程度越大。In view of the poor high temperature resistance of common adhesives for structural reinforcement,a new type of high strength adhesive(epoxy carrier film adhesive)was used.Temperature spectrum of dynamic mechanical properties of the film adhesive was obtained by dynamic thermo mechanical analysis.Nine CFRP laminate/steel double lap joint specimens were fabricated and stretched at three environmental temperatures.The failure modes,bearing capacity and force transfer rule of the specimens were also studied.The results show that the glass transition temperature of the film adhesive based on storage modulus is 69.5℃,which is much higher than that of common adhesives.The ultimate bearing capacity of specimens decreases with the increase of temperature.The ultimate bearing capacity of specimens at 70℃decreases by 8.4%only compared with that at 40℃,the high temperature resistance of the film adhesives is good.The higher the temperature is,the longer effective bond length of specimens is.The appropriate bond length of CFRP should be selected according to the environmental temperature in actual engineering reinforcement.During the loading process,the peak shear stress gradually moves to the end of CFRP laminate.Under the same load(e.g.150 kN),the higher the temperature is,the greater the degree of interface debonding is.

关 键 词：胶膜 高温 双搭接接头 玻璃转化温度 有效粘结长度 

分 类 号：TB332[一般工业技术—材料科学与工程]