(1 清华大学土木工程系 北京 100084； 2 英国爱丁堡大学工程与电子学院 爱丁堡 EH93JN)
［提要］ 剥离破坏是外贴FRP片材加固混凝土梁主要的破坏形式。回顾了对外贴FRP混凝土梁的试验研究、有限元分析和国内外现有的受剪剥离承载力计算公式。讨论了斜裂缝宽度分布规律，建立了FRP滑移分布模型，在此基础上分析了受剪剥离破坏时FRP的应力分布，讨论了FRP抗剪贡献与粘结长度、粘结方式等参数之间的关系。提出了受剪剥离承载力计算公式，与大量试验结果的对比表明，给出的设计建议公式与试验结果吻合良好，可供设计应用参考。
［关键词］ FRP 受剪剥离 加固 混凝土梁 斜裂缝 受剪承载力
Debonding Failure Strength in RC Beams Strengthened with FRP for Shear/Lu Xinzheng1,Ye Lieping1,Chen Jianfei2,Li Tianhong1(1 Department of Civil Engineering,Tsinghua University,Beijing 100084,China; 2 Institute for Infrastructure and Environment,School of Engineering and Electronics,Edinburgh University,EH93JN)
Abstract:Debonding failures always take place in RC beams strengthened with externally bonded FRP against shear failure.Whilst the shear capacity may continue to increase after debonding for FRP wrapped beams,FRP debonding represents the ultimate failure state for most beams strengthened with U jacketing and sidebonding.It presents a review of existing studies on debonding failure.Using a rigorous local FRPtoconcrete bondslip model,the stress distribution in FRP along the critical shear crack is investigated by assuming several crack width distributions.A new design model is proposed.Compared with test data,the model has similar accuracy but is slightly more conservative than Chen and Tengs model.
Keywords:FRP; debonding; shear strengthening; reinforced concrete beam; shear strength