- 摘 要
-
(1 清華大學(xué)土木工程系 北京 100084; 2 英國愛丁堡大學(xué)工程與電子學(xué)院 愛丁堡 EH93JN)
[提要] 剝離破壞是外貼FRP片材加固混凝土梁主要的破壞形式?;仡櫫藢ν赓NFRP混凝土梁的試驗研究、有限元分析和國內(nèi)外現(xiàn)有的受剪剝離承載力計算公式。討論了斜裂縫寬度分布規(guī)律,建立了FRP滑移分布模型,在此基礎(chǔ)上分析了受剪剝離破壞時FRP的應(yīng)力分布,討論了FRP抗剪貢獻(xiàn)與粘結(jié)長度、粘結(jié)方式等參數(shù)之間的關(guān)系。提出了受剪剝離承載力計算公式,與大量試驗結(jié)果的對比表明,給出的設(shè)計建議公式與試驗結(jié)果吻合良好,可供設(shè)計應(yīng)用參考。
[關(guān)鍵詞] FRP 受剪剝離 加固 混凝土梁 斜裂縫 受剪承載力
Debonding Failure Strength in RC Beams Strengthened with FRP for Shear/Lu Xinzheng1,Ye Lieping1,Chen Jianfei2,Li Tianhong1(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 sidebonding.It presents a review of existing studies on debonding failure.Using a rigorous local FRPtoconcrete bondslip 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 Tengs model.
Keywords:FRP; debonding; shear strengthening; reinforced concrete beam; shear strength