Strength and Deformation Capacity of Tension and Flexural RC Members Containing Steel Fibers

Abstract

A misnomer exists within the literature on the topic of ductility (deformation capacity) in steel fiber reinforced concrete (SFRC) members subjected to flexure. Several studies report that the addition of fibers to reinforced concrete (RC) beams subjected to flexure increases the deformation capacity of the members. This can be true for normally longitudinally reinforced concrete beams; however, a few studies have shown this not to be the case, particularly for lightly reinforced concrete members containing even low amounts of steel fibers. It has been observed that failure may occur at far lower deformations in structural concrete members containing steel fibers than without the fibers. This paper presents a system of rational and mechanically consistent expressions capable of predicting the entire load-deformation relationship for SFRC tension and one-way flexural members. The model is also capable of determining whether the addition of fibers to the RC member may lead to a failure mode governed by rupture of the longitudinal reinforcing bars or crushing of the concrete.