Slant shear bond strength between self compacting concrete and old concrete

This experimental investigation aims to study the bond strength between old and new self-compacting concrete (SCC). The first part presents the factors affecting slant shear bond strength between old concrete and new self-compacting concrete. The studied parameters are compatibility between old concrete and new SCC through variation of concrete compressive strength and concrete stiffness, type of bonding agent, roughness of old concrete, and the effect of adding latex and polypropylene fiber to self-compacting concrete. In the second part, the proper specimen of slant shear test is studied. From the test results, cylindrical specimens with 150 mm diameter and 300 mm height have a minimum coefficient of variation compared with other studied shapes. The concrete compressive strength overlay self-compacting concrete, roughness of old concrete configuration, adding latex and using polypropylene fiber have a significant effect on slant shear bond strength. In addition, the prism specimen represents more reliable value of slant shear strength than cylinder specimen.