Authors

Abstract

This study investigates experimentally the strengthening of reinforced concrete deep
beams using steel fibers. The experimental work could be divided in two parts, the
first part consists of casting and testing six deep beams without web opening and the
second part consists of casting and testing six deep beams with web openings to show
the effect of volume of steel fibers on the behavior of the deep beams with and
without 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 these
parameters 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 steel
fibers in deep beams with web openings.
The results obtained from the experimental work [solid deep beams and deep beams
with web openings], demonstrate that when the steel fiber volume- fraction is
increased, the ultimate loads are also increased. The effect of steel fibers increases as
the (a/d) ratio is decreased. In addition, the experimental work on deep beams without
web opening showed that when the steel fiber volume-fraction is kept constant, the
ultimate loads are increased as the (a/d) ratio is decreased. On the other hand, the
percentages of increase in ultimate loads become higher as the steel fiber volumefraction
is increased from 0.0% to 0.5% and 1.0%. However, the effect of decreasing
the (a/d) ratio on the ultimate and cracking loads of the deep beams with web
openings was not significant.