高温下双搭接钢-CFRP板胶粘界面力学性能试验

高温环境下钢-碳纤维增强聚合物复合材料(CFRP)板的胶粘界面是CFRP粘贴加固钢结构的薄弱环节。为掌握温度对钢-CFRP板胶粘界面力学性能的影响，制作了双搭接接头试件，开展了3种胶粘剂在4种温度下(25℃、55℃、70℃和90℃)的静力拉伸试验。探索了接头试件的破坏模式、荷载-位移关系、CFRP板表面应变分布、界面剪应力分布和粘结-滑移关系等。结果表明:当温度低于55℃时，试件的破坏模式与胶粘剂种类相关性更大，当温度高于70℃时，不同胶粘剂的破坏模式具有相似性，且均出现了CFRP板撕裂。温度对不同胶粘试件的承载力影响存在差异，HJY-4105高韧性环氧树脂结构胶粘剂(HJY胶)试件的承载力随温度的升高而增大，LICA-100A/B 环氧树脂结构胶粘剂(LICA胶)试件的温度稳定性较差，Sikadur-30 CN双组份环氧结构加固碳板胶(SIKA30胶)试件在55℃时承载力最高。随着温度升高，胶粘层的剪切强度、界面剪应力峰值和剪切刚度下降，胶粘剂的延性增加，峰值剪应力不影响试件的抗拉强度。温度对粘结-滑移关系的影响显著，HJY胶随着温度的升高，粘结-滑移本构的延性增加，破坏模式由脆性破坏变为延性破坏。研究表明:合理的耐高温胶应用于钢结构加固，能适应自然高温环境的不利影响。 

Experimental study for the adhesive interface mechanical properties of double lapped steel-CFRP plate at high temperature

The bond interface between steel and carbon fiber reinforced polymer(CFRP) plate is the weak part of steel structure strengthened by CFRP at high temperature. In order to explore the influence of temperature on the adhesive mechanics of steel to CFRP joints, some double lapped joint specimens were manufactured, and static tensile tests were conducted with three types of adhesives under four kinds of temperatures, which include 25℃,55℃, 70℃ and 90℃. Thereafter, the failure modes, the load-displacement relationships, the strain distribution of CFRP plates and the bond-slip relationship of specimens were explored respectively. The results show that the failure modes of specimens are more related to the type of adhesive, when the temperature is lower than 55℃;but the failure modes of different adhesives are similar, and all the CFRP plates occur fracture when the temperature is higher than 70℃. The influence of temperature on the capacity of bond specimens is different, which depends on the type of epoxy resin adhesive. The capacities of HJY-4105 high toughness epoxy structural adhesive(HJY adhesive) specimens increase with the temperature increasing, and the capacities of LICA-100 A/B epoxy structural adhesive(LICA adhesive) specimens are instability under different temperatures, and Sikadur-30 CN twocomponent epoxy structure reinforced carbon plate adhesive(SIKA30 adhesive) specimens have the highest capacity at 55℃. The shear strength of adhesive layer, the peak shear stress of interface and the shear stiffness decrease as the temperature increasing, but the ultimate tensile strength has no concern with the peak shear stress. Temperature has a significant effect on the bond-slip relationship, the ductility of the bond-slip constitutive of HJY adhesive increases with the increase of temperature, and the failure mode changes from brittle failure to ductile failure.The research shows that the reasonable high temperature resistant adhesive applied to steel structure reinforcement can adapt to the adverse effects of the natural high temperature environment.