Bond behaviour of reinforced recycled concrete after rapid freezing-thawing cycles

摘要

Pull-out test was conducted to investigate the bond behaviour between recycled aggregate concrete and steel bar after rapid freezing-thawing cycles in fresh water and saline water. The test variables were number of freezing-thawing cycles (0, 25, 50 and 75), diameter of steel bar (14, 18 mm) and freezing-thawing medium (fresh water, saline water). According to the test results, the effect of freezing-thawing cycles, diameter of steel bar and freezing-thawing medium on the bond behaviour was analysed. It was found that the bond strength between steel bar and recycled aggregate concrete decreases as the freezing-thawing cycles increased, and after the same number of rapid freezing-thawing cycles, the loss of bond strength in saline water was greater than that in fresh water. Moreover, the loss of compressive strength was greater than the loss of bond strength between steel bar and recycled aggregate concrete after the same number of rapid freezing-thawing cycles in saline water.