Experimental study on bond strength between FRP and concrete||FRP复合材料与混凝土的粘结强度试验研究

FRP复合材料与混凝土的粘结强度是混凝土结构外粘FRP板材这一加固新技术的重要研究课题。本文首先采用FRP板-混凝土块搭接接头的单剪试验方法,考虑FRP板的搭接长度、支座高度变化、试件对中偏位、FRP板与混凝土块的宽度比等因素,对FRP与混凝土的粘结强度进行了深入研究。然后利用试验结果与最近提出的陈-滕粘结强度公式作了比较研究。研究结果表明:(1)粘结破坏有FRP剥离破坏和混凝土拉剪破坏两种形式;(2)FRP板的搭接长度、试件对中偏位、FRP板与混凝土块的宽度比等因素对粘结强度有显著影响,支座高度变化也有一定影响;(3)粘结强度不小于“有效粘结长度”时,陈-滕粘结强度公式具有较高精度。||The bond strength between fiber rein forced plastic /polymer composites(FRP)sheet and concrete was studied by experiment on a simple shear test s et-up with emphasis on the effects of the bond length,support height,loading offset and FRP-to-concrete width ra tio.The test results were compared w ith those obtained from the Chen and T eng’s bond strength formulas.Following c onclusions are drawn from this study:(1)there are two kinds of failure modes,namely FRP debonding failure and con crete tension-shear failure;(2)the bond length,loading offset and FRP-to-concrete width ratio have significant effects on bond strength while the support height also has certain effect;(3)the results obtaind from Chen-Teng’ s bond strength formula agree well wi th the test results,provided the total bond length is no less than the effective bond len gth.