为了研究纤维增强聚合物(fiberreinforced polymer,FRP)加固梁的FRP-混凝土界面脱胶破坏过程,本文将混凝土梁和FRP板均视为线弹性的欧拉一伯努利梁fEuler-Bernoulli beams),且两者通过粘结层胶结在一起.对于FRP-混凝土结构,有两种形式的脱胶破坏:板端脱胶破坏和跨中裂缝导致的脱胶破坏.对于FRP-混凝土梁,利用合理的粘结模型按第2种脱胶失效形式,详细讨论了FRP-混凝土界面的脱胶过程,得到了不同阶段的胶结滑移、界面剪应力和FRP轴向力的解析解.实验研究验证了理论分析的结果,参数研究进一步探讨了胶结长度和粘结层厚度对于FRP.混凝土界面脱胶行为的影响.
In order to investigate the debonding process of the interface between the FRP(fiber reinforced poly- mer) and the concrete for the FRP strenthening structure, both the strengthened beam and the strengthening FRP are modeled as two linearly elastic Euler-Bernoulli beams bonded together through a thin adhesive layer. For the FRP-concrete structure, there are two types of debonding failures: The plate end debonding and the intermediate crack (IC) induced debonding. For the second type debonding failures in the FRP-concrete bonded joint model where the FRP plate is subject to tension at both ends, the debonding process of the FRP-concrete interface is discussed in detail, and the closed-form solutions of the bond slip, the interface shear stress, and the axial force of the FRP in different stages are obtained. The results of theoretical analyses are confirmed by experiments. Parametric studies are further carried out to investigate the effect of the thickness of the adhesive layer and the bond length on the bond behavior of the FRP-concrete interface.