大温差循环作用下CFRP板-钢界面黏结性能试验  

Study of Interfacial Bond Between Carbon Fiber Reinforced Polymer Plates and Steel Under Large Temperature Difference Cycles Action

作　　者：任翔[1] 张泽亚 孙亚民 韩琇珠 陈少杰[1] 周浩男 REN Xiang;ZHANG Ze-ya;SUN Ya-min;HAN Xiu-zhu;CHEN Shao-jie;ZHOU Hao-nan(School of Architecture and Civil Engineering,Xi'an University of Science and Technology,Xi'an 710054,Shaanxi,China;School of Civil Engineering,Xi'an Traffic Engineering Institute,Xi'an 710300,Shaanxi,China;Organization Department of Chang'an District,Xi'an 710100,Shaanxi,China)

机构地区：[1]西安科技大学建筑与土木工程学院,陕西西安710054 [2]西安交通工程学院土木工程学院,陕西西安710300 [3]中共西安市长安区委组织部,陕西西安710100

出　　处：《中国公路学报》2024年第10期116-127,共12页China Journal of Highway and Transport

基　　金：国家自然科学基金项目(51408484,52108246);榆林市科技计划项目(CXY-2022-157)。

摘　　要：温差循环环境下,碳纤维增强复合材料(CFRP)板加固钢结构的黏结界面受到不利影响。为探究大温差循环作用对CFRP加固开裂钢试件界面黏结性能的影响,制作了黏结剂试件和CFRP-钢试件,拟定高温为60℃,低温为25℃温差循环工况,开展了黏结剂和CFRP-钢试件的环境、拉伸试验,分析黏结剂和CFRP-钢试件的破坏模式、承载能力、界面剪应力分布、黏结-滑移关系等。结果表明:在大温差循环初期,黏结剂的抗拉强度和弹性模量略有提升,但随着温差循环次数的增加,黏结剂和CFRP-钢试件的极限荷载、界面峰值剪应力、刚度、断裂能逐渐降低。CFRP-钢试件主要表现为界面剥离和纤维剥离的混合破坏,荷载-位移曲线和黏结-滑移曲线无下降段,呈现脆性破坏特征。综上分析表明,大温差循环作用下不仅导致CFRP-钢试件界面胶层强度降低,也使黏结剂与CFRP板及钢板间黏结性能降低,二者是引起CFRP-钢试件承载力下降的主要因素。基于CFRP-钢试件界面黏结参数,建立了CFRP-钢试件黏结-滑移关系退化模型,可预测温差循环作用后试件界面剪应力与滑移量的关系,为提高加固设计的耐久性提供了重要参考。In a thermal cycling environment,the bonding interface of carbon fiber-reinforced plastics(CFRP)(commonly used to reinforce steel structures)is adversely affected.To investigate the influences of large temperature difference cycling on the bonding performance of CFRP-strengthened cracked steel specimens,adhesive specimens,and CFRP-steel specimens were fabricated.The highest and lowest temperatures for the cyclic thermal conditions were set to 60℃and 25℃,respectively.Environmental and tensile tests were conducted on the adhesive specimens and CFRP-steel specimens to analyze the failure modes,load capacity,interfacial shear stress distribution,and bonding-slip relationship.The results indicate that,during the initial stages of large temperature difference cycling,the tensile strength and elastic modulus of the adhesive exhibit a slight increase.However,as the number of cycles increases,the ultimate load,peak interface shear stress,stiffness,and fracture energy of both the adhesive and CFRP-steel specimens progressively decline.The CFRP-steel specimens primarily display a mixed failure mode involving interface peeling and fiber delamination,with no descending sections in the load-displacement and bond-slip curves,reflecting brittle failure characteristics.In conclusion,large temperature difference cycling not only reduces the adhesive layer strength at the CFRP-steel interface but also diminishes the bond performance between the adhesive,CFRP plates,and steel plates.These two factors are the main contributors to the reduction in load-bearing capacity of the CFRP-steel specimens.Based on the bond-slip parameters of the CFRP-steel interface,a degradation model of the bond-slip relationship was established,allowing for the prediction of the interface shear stress and slip under temperature cycling.This provides valuable insights for enhancing the durability of reinforcement designs.

关 键 词：桥梁工程 CFRP加固 温差循环 黏结性能 承载能力 剪应力 

分 类 号：U445.6[建筑科学—桥梁与隧道工程]