以100％再生粗骨料取代天然碎石，以钢筋直径16 mm和20 mm锚固长度5 d和10 d为变动因素制作中心拔出试件。采用快冻法进行冻融循环试验，研究不同冻融循环后再生混凝土抗压强度、极限荷载和极限黏结应力的变化规律，通过对黏结界面扫描电镜观察，从微观角度分析再生混凝土冻融破坏原因。试验结果表明：冻融循环后再生混凝土抗压强度下降，极限荷载和极限黏结应力随冻融循环次数的增加而减小，是由于再生混凝土内部受冻胀破坏所致。%The coarse aggregate was insteaded by using 100%recycled coarse aggregate. Steel bar diameter 16 mm and 20 mm anchor-age length of 5 d and 10 d were used as two variable factors to make center of the pull-out specimen. The experiment of freezing and thawing was conducted by using fast freezing-thawing cycling method. The influence law of mechanical properties of compressive strength,ultimate load and ultimate bond stress were studied. The bonding interface was looked by employing scanning electron micro-scope( SEM)and the damage reasons of failure were analysed from microscomic perspective. The test result show that the compressive strength of recycled concrete descend during the process of freezing and thawing. With the increasing of freezing and thawing cycles,the ultimate load and ultimate bond stress decreased. The reason was that frozen-heaving damage leaded to the damage of the recycled concrete.
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