Use of Welded Wire Reinforcement as Lateral Reinforcement in Concrete Beams: Part 2—Flexure
Abdelaziz Younes, Sami W. Tabsh, and Yazan Alhoubi
Appears on pages(s):
beam confinement; ductility; flexure; reinforced concrete (RC); stiffness; welded wire reinforcement (WWR)
Past studies had shown that welded wire reinforcment (WWR) can be used as an effective alternative to stirrups in resisting shear in reinforced concrete beams. Such a form of reinforcement reduces labor, decreases the time required to assemble the steel cage, and eliminates anomalies in the fabrication and placement of the stirrups. This study investigated the flexural behavior of reinforced concrete beams transversely reinforced with closed steel cagesmade by cold-formed WWR sheets. To accomplish the goals of the study, seventeen 2 m (6.6 ft) long beams with 200 x 300 mm (8 x 12 in.) cross sections were tested under a two-point load configuration with consideration of different wire diameters (4, 6, and 8 mm [0.16, 0.24, and 0.32 in.]), grid openings (25, 50, and 100 mm [1, 2, and 4 in.]), and longitudinal steel reinforcement ratios (0.77 and 1.92%). A comparison between the test results of WWR-reinforced beams and their equivalent stirrup-reinforced beams was performed. The experimental study was accompanied by a theoretical component using the flexural design provisions in ACI 318. Compared to corresponding beams having stirrups equivalent tothe vertical wires of the WWR, the WWR-reinforced beams had on average 20% more flexural capacity, just about the same stiffness at service load, and 10% less flexural ductility. The average experimental-to-nominal flexural capacity based on ACI 318 for concrete beams reinforced with WWR is equal to 1.15, which indicates that the Code can be reliably used to predict the bending moment capacity of such beams. The study recommends always using longitudinal reinforcing bars in WWR-reinforced beams and not relying solely on the longitudinal wires of the WWR for resisting flexure.