Evaluation of the Bond Shear Strength and Corrosion Resistance of Concrete with Setting Retarder

In this study, the bond shear strength and corrosion resistance of concrete with setting retarders were evaluated. For this, slant shear, bi-surface, and accelerated corrosion tests were conducted. The variables considered included the proportion of the setting retarder (0 and 1%), surface treatments of concrete (as-cast, chipping, and brushing), curing hours (8, 16, and 24 h), and concrete cover depths (20, 30, and 45 mm). Consequently, the bond shear strength of concrete with the retarder showed a higher value than that of normal concrete. Moreover, an increase in curing hours resulted in a higher value of the bond shear strength. Furthermore, the addition of a retarder in concrete increased corrosion resistance. Based on the test results, the addition of a setting retarder is believed to be a suitable solution to address the bond shear strength and durability issues that may arise at the interface of delayed concrete placement.