Effect of Steel Fiber on The Behavior of Deep Beams With and Without Web Opening

Abstract

This study investigates experimentally the strengthening of reinforced concrete deepbeams using steel fibers. The experimental work could be divided in two parts, thefirst part consists of casting and testing six deep beams without web opening and thesecond part consists of casting and testing six deep beams with web openings to showthe effect of volume of steel fibers on the behavior of the deep beams with andwithout web opening on ultimate load, deflection, with various shear span to depth(a/d) ratios [variable of clear shear span].On the other hand, the effects of theseparameters on the behavior and capability of deep beams with constant steel fiber –volume fraction are obtained by using three groups of beams having steel fiber–volume fractions of 0.0%, 0.5%, 1.0% and studying the effect of the presence of steelfibers in deep beams with web openings.The results obtained from the experimental work [solid deep beams and deep beamswith web openings], demonstrate that when the steel fiber volume- fraction isincreased, the ultimate loads are also increased. The effect of steel fibers increases asthe (a/d) ratio is decreased. In addition, the experimental work on deep beams withoutweb opening showed that when the steel fiber volume-fraction is kept constant, theultimate loads are increased as the (a/d) ratio is decreased. On the other hand, thepercentages of increase in ultimate loads become higher as the steel fiber volumefractionis increased from 0.0% to 0.5% and 1.0%. However, the effect of decreasingthe (a/d) ratio on the ultimate and cracking loads of the deep beams with webopenings was not significant.