Title: Bond between Normal Strength and High-Strength Concrete (HSC) and Reinforcing Bars in Splices in Beams

Author(s): M. Reza Esfahani and B. Vijaya Rangan

Publication: Structural Journal

Volume: 95

Issue: 3

Appears on pages(s): 272-280

Keywords: beams; bond (concrete to reinforcement); high-strength concretes; reinforced concretes; reinforcing steels; splices

DOI: 10.14359/545

Date: 5/1/1998

Abstract:
This paper presents the second part of a study on bond. It reports on the influence of several parameters on bond in splices. The parameters covered are concrete strength, splice length, concrete cover, ratios between side cover, bottom cover, and the spacing between the spliced bars, rib face angle of the reinforcing bar, and admixtures in the concrete mix. The study was conducted in two stages. In the first stage, an analytical equation was developed to calculate the bond strength of splices in normal strength concrete. The mean value of test/calculated bond strength for the proposed equation is 1.007 with a standard deviation of 0.084. These values indicate a significant improvement in the calculation of the bond strength when compared to other proposed equations. The second stage of the research involved tests on twenty two beams made of high-strength concrete (HSC). In each beam, the tensile steel was spliced in the constant moment zone. The test strengths are compared with the calculated values. Good correlation between calculated and test strengths of splices in the case of HSC is found.