FRP加固钢筋混凝土梁受弯剥离破坏是一种非常常见的破坏形式.首先基于微观尺度有限元分析,对受弯剥离破坏的机理进行了研究,提出了一个受弯剥离的双重剥离破坏准则,以及相应的界面粘结滑移关系,使得受弯剥离可以由基于普通弥散裂缝模型的混凝土单元来加以模拟,并开发出了相应的FRP-混凝土界面单元模型.将该界面单元嵌入通用有限元程序MSC.MARC,对45根受弯剥离破坏的试验梁进行了有限元分析。分析结果表明,提出的计算模型与试验结果吻合良好,可以真实模拟受弯剥离破坏过程.
A finite element (FE) model to simulate the intermediate crack (IC) debonding of RC beams flexually strengthened with externally bonded FRP plates is presented. A dual debonding criterion is proposed so that IC debonding can be predicted with the common smeared crack approach for concrete. Based on meso-scale FE results, proper bond-slip models for the interface between FRP and concrete are subsequently proposed. The FE model is implemented into the FE package MSC.MARC. Through comparisons with the experimental results of 45 beams, the proposed method is shown to provide accurate predictions of IC debonding failures.