Six groups of average bond-slip curves between full natural aggregate/full recycled aggregate concrete and rebar and the rebar's strain along the embedment length were investigated by means of inner-embedded gauges,considering different distances among stirrups.The test data were used to calculate the bond stress,slip,and bond-slip curve was obtained at different locations.Finally,the bond stress distribution function between recycled concrete and steel rebar was established,and the mechanics of stirrups affected on bond distribution function was also analyzed.The results show that specimens without stirrups exhibit a higher bond stress near the load end than those stress near the un-load end.For specimens with stirrups,with the reduction of distance between stirrups,the ultimate bond strength and peak slip increase,the descending blanch of bond-slip curve becomes flatter,and the bond stress distribution becomes uniform as well.In addition,recycled coarse aggregate has little effect on the bond stress distribution.%通过改变箍筋间距,采用钢筋开槽内贴片方法,测试全天然骨料和全再生骨料共6组钢筋混凝土构件的平均黏结-滑移曲线及锚固段内不同位置处的钢筋应变.基于试验结果,计算不同锚固位置处钢筋与混凝土的黏结应力和相对滑移,得到相应位置的黏结-滑移曲线.分析箍筋约束对再生混凝土-钢筋黏结应力分布的影响机理,并建立再生混凝土与钢筋间黏结应力分布函数模型.研究结果表明:未配箍构件的加载端黏结应力大于自由端黏结应力;构件配箍筋后,平均极限黏结强度提高,峰值滑移显著增加,平均黏结-滑移曲线下降段变平缓,且随着箍筋间距减小,锚固段黏结应力分布逐渐均匀;再生粗骨料对钢筋混凝土的黏结应力分布影响较小.
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