针对2种用于结构修复的纤维水泥基材料(超高韧性水泥基复合材料UHTCC和钢纤维混凝土SFRC),以钢筋锈蚀率(质量分数,下同)为参数,通过中心拉拔试验,研究了清理干净的锈蚀钢筋与纤维水泥基材料的黏结性能.结果表明:由于纤维的桥接作用,UHTCC和SFRC试件均呈现出劈裂-拔出破坏模式;随着钢筋锈蚀率的增大,UHTCC试件的相对黏结应力-平均滑移曲线下降段渐趋平缓,SFRC试件的曲线下降段斜率基本保持不变;在相近的锈蚀水平下,UHTCC试件的黏结强度和残余黏结强度均高于SFRC试件;当钢筋锈蚀率约为14％时,2种试件的黏结强度分别下降至初始强度的81％和88％;钢筋锈蚀对纤维水泥基材料的残余黏结强度影响较小.%Interfacial bond behavior between corroded rebar cleaned up and fiber reinforced cementitious materials were investigated through central pullout tests.Two kinds of materials were used in the tests,including ultra-high toughness cementitious composite (UHTCC) and steel fiber reinforced concrete (SFRC).The variable considered was corrosion ratio.The experimental results reveal that all the UHTCC and SFRC specimens show splitting-pullout failure mode depending on the fiber bridging action.With the increasing corrosion ratio,a gentle descending branch of relative bond stress-average slip curves is obtained for UHTCC samples whereas the slope of descending branch is almost comparable to SFRC specimens.At a similar corrosion ratio,UHTCC sample has higher bond strength and residual bond strength compared with SFRC specimen.When the corrosion ratio is high up to about 14％(by mass),the bond strength descends to 81％ and 88％ of the initial strength for UHTCC and SFRC samples,respectively.Moreover,the effect of corrosion on the residual bond strength is little.
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