Title: Indirect Loading on Beams with Short Shear Spans

Author(s): S. M. Fereig and K. N. Smith

Publication: Journal Proceedings

Volume: 74

Issue: 5

Appears on pages(s): 220-222

Keywords: beams (supports); cracking (fracturing);deep beams; deflection; loads (forces); reinforced concrete; shear strength; span-depth ratio; web reinforcement.

DOI: 10.14359/11005

Date: 5/1/1977

Abstract:
A study of the effect of loading and supporting conditions on the behavior and ultimate shear strength of beams with short shear spans is presented. Previous experimental work by the authors has been extended to include a shear span-to-depth ratio = 2. The overall findings of the investigation are summarized. For directly loaded beams (forces applied on the top and reactions on the underside) without web reinforcement the nominal shear stress at failure increases as the shear span-to-depth ratio decreases below approximately 2.5; indirectly loaded beams, in which the loads are applied via shear on the sides of the members, exhibit a much smaller gain in strength and the increase only occurs below a shear span-to-depth ratio of about 1.5. The addition of web reinforcement to the short shear span beams generally reduced crack widths, tensile steel strains, and deflections, but for the reinforcement ratios employed, there was only a small effect on the ultimate strength of the directly loaded beams compared with a significant strength contribution in the indirect case.