Bond strength of epoxy coated bar splices confined with nominal lateral reinforcement

Abstract

Fusion bonded epoxy coating is one of the methods used to protect steel against corrosion. The primary objective of this research reported in this paper is to evaluate the bond strength of epoxy coated bar splices confined with lateral reinforcement. Six full scale beams specimens, designed to fail in bond- splitting mode, were tested in positive bending. Each beam was reinforced with bars spliced in the constant moment region at mid span. The main variables were the amount of transverse reinforcement in the splice region and the coating to the bar. Test results indicate that transverse reinforcement improves the bond strength of coated bars and the ductility of the beams. The bond strength of coated bars is 93%, 72% and 59% of uncoated bars for confinement indices of 1.8, 1.4 and 1.26 respectively. Moreover, a bond reduction factor of 1.35 is suggested for use in code in place of 1.5,when the confinement index is greater than 1.4.