The effects of post-fire-curing on the bond strength recovery of fire-damaged concrete were investigated in this study. Normal strength concrete (NSC) and high-strength concrete (HSC) specimens with deformed steel bars were prepared respectively. We measured the bond strength of unheated NSC and HSC, and exposed other NSC and HSC specimens to high temperatures of 300℃, 400℃, and 500℃, respectively for 120 minutes. Following by rapid cooling with water, the bond strengths of heated NSC and HSC were measured instantly without re-curing, the remains were cured in water for 28 days, or further in the air of 20℃, 60% R.H. for 56 ~62 days. After the re-curing, the pull-out tests were conducted. The test results indicate that the post-fire-curing contributes to a substantial bond strength recovery of heated concrete. The longer the re-curing in water, the greater the recovery extent. At 90 days of re-curing age, the bond strength rose up to around 77% for NSC, and around 70% for HSC, respectively.
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