A misnomer exists within the literature on the topic of ductility (deformation capacity) in steel fibre reinforced concrete (SFRC) members subjected to flexure. Several studies report that the addition of fibres to reinforced concrete 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 fibres. It has been observed that failure may occur at far lower deformations in structural concrete members containing steel fibres than without the fibres. 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 fibres to the reinforced concrete member may lead to a failure mode governed by rupture of the longitudinal reinforcing bars or crushing of the concrete.

The structural behavior of concrete hinges under general loading is far from being properly understood, which is to a large extent due to the lack of pertinent experimental data. This paper contributes to filling this knowledge gap by presenting and discussing the results of an experimental campaign on one‐way Freyssinet concrete hinges. Seven large‐scale concrete hinges were tested in the Large Universal Shell Element Tester, which allowed the investigation of their behavior under general loading by all six stress resultants. A combination of digital image correlation and distributed fiber optic measurements allowed a deeper insight into the structural behavior of the specimens. The tested hinges could sustain very high axial stresses exceeding 4.5 times the uniaxial concrete compressive strength, large rotations of over 60 mrad, and shear stresses in transverse and longitudinal directions up to 2.24 times the axial compressive stress. The resistance to bending moments about the strong axis and torques also proved to be significant. A moderate amount of reinforcement crossing the hinge throat considerably increased the shear resistance at low axial stresses and produced a ductile shear behavior.

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