Title: Shear Strength of Steel Fiber-Reinforced Concrete Beams without Stirrups

Author(s): Yoon-Keun Kwak, Marc O. Eberhard, Woo-Suk Kim, and Jubum Kim

Publication: Structural Journal

Volume: 99

Issue: 4

Appears on pages(s): 530-538

Keywords: beam; cracking; shear strength

DOI: 10.14359/12122

Date: 7/1/2002

Abstract:
Twelve tests were conducted on reinforced concrete beams with three steel fiber-volume fractions (0, 0.5, and 0.75%), three shear span-depth ratios (2, 3, and 4), and two concrete compressive strengths (31 and 65 MPa). The results demonstrated that the nominal stress at shear cracking and the ultimate shear strength increased with increasing fiber volume, decreasing shear span-depth ratio, and increasing concrete compressive strength. As the fiber content increased, the failure mode changed from shear to flexure. The results of 139 tests of fiber-reinforced concrete beams without stirrups were used to evaluate existing and proposed empirical equations for estimating shear strength. The test population included beams with a wide range of beam properties, but most of the beams were small. The evaluation indicated that the equations developed by Narayanan and Darwish and the equations proposed herein provided the most accurate estimates of shear strength and the onset of shear cracking. For the proposed procedure, the ratio of the measured strength to the calculated strength had a mean of 1.00 and a coefficient of variation of 15%.