Correlation between Flexural–Tensile Performance of Concrete Reinforced with Hooked-End Steel Fibers Using US and European Standards

Abstract

ACI 318 and the fib Model Code 2010 prescribe recommendations for the design of steel fiber–reinforced concrete (SFRC) using performance measured with a four-point bending test (4PBT) per the ASTM C1609 US standard and a three-point bending Test (3PBT) per the EN 14651 European standard, respectively. Different assumptions of the test methods hinder the comparison and direct correlation of studies performed using European and US standards. This study determined the residual flexural tensile performance of 40 SFRC beams using 3PBTs and 4PBTs. The study variables were the dosage (0, 20, 40, and 60 kg/m3), the number of hook ends (1, 1.5, and 2), and the tensile strength of the steel fibers. The study assessed the effect of number of hook ends and reinforcement index of steel fibers on the residual strength from 3PBTs and 4PBTs. A model is proposed to correlate the residual tensile performance of the SFRC measured using tests procedures prescribed by European and US standards. The proposed model includes the influence of strain hardening on the relationship between residual strength from 3PBT and 4PBT.