端部嵌贴CFRP加固混凝土结构有限元分析

Finite element analysis of concrete structure reinforced by terminal embedded the CFRP strips

为解决表面粘贴和表层嵌贴CFRP加固混凝土结构的端部剥离问题,本研究提出一个新型加固方法—端部嵌贴加固(TE),设计了不同加固长度的单剪拔出试验,对比分析其黏结承载力、破坏模式及CFRP应变分布情况。运用ABAQUS有限元分析软件对试样进行非线性数值分析,研究了混凝土等级、槽尺寸大小等各因素对模型界面黏结性能的影响。研究结果表明:采用Spring2非线性弹簧,实现CFRP板条、混凝土与树脂胶之间的滑移是可行的。端部嵌贴方法能有效提高界面黏结性能,嵌贴段锚固作用较好,但沿板宽方向与中央部分的黏结应力不一致。采用合适的槽宽,提高混凝土等级,能有效提高端部嵌贴CFRP与混凝土的界面黏结性能。

To solve the end peeling problem of externally bonded and near surface mounted CFRP reinforced concrete structures,a new terminal embedded(TE)reinforcement method was proposed in the present study.Single shear pull-out tests with different reinforcement lengths were designed to compare and analyze the bonding capacity,the failure mode and the CFRP strain distribution.Nonlinear numerical analysis is conducted by using ABAQUS software to study the effects of various factors such as concrete grade and slot size on the bonding behavior of model interface.The test results show that the slippage between CFRP strips,concrete and resin glue can be simulated by using the Spring2 nonlinear springs.The TE method can effectively improve the interface bonding performance.The embedding section shows good anchoring performance.However,the bonding stress along the width of CFRP strip is not uniform.It is suggested that proper groove width and high-grade concrete can improve the bonding performance at the interface between the CFRP strips and the concrete.