الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
The shear resistance of concrete structures is a complex
phenomenon due to the influence of several mechanisms and the
interactions between these mechanisms. Theoretical models for the
behaviour of concrete beams subjected to shear were found to
considerably differ from one another in their formulation, and it
was found that no existing model was able to accurately account for
all the factors influencing concrete shear behaviour and the
interactions between these factors. The shear design provisions
founded in many codes of practice globally used by designers are
based on an empirical model of concrete shear behaviour and are
augmented using empirical data. Most codes of practice commonly
used by designers do not take into consideration the effect of widthto-depth
ratio (aspect ratio) as well as the shape effect and also
neglect the contribution of dowel action of longitudinal bars.
The research program included in thesis, evaluates the effect
of cross section shape on shear behaviour of reinforced concrete
beams. The main factors studied in this research were: the cross
section shape of the beams, the width-to-depth ratio (aspect ratio),
shear reinforcement ratio, and the longitudinal tensile reinforcement ratio. Experimental tests was carried out to study the effect of these
factors on the behavior of RC beams in shear, besides some
analytical studies were done and compared with the experimental
results.
The experimental program of this research comprised of six
medium-scale reinforced concrete beam specimens tested up to
failure under static loading conditions. For all beam specimens, the
overall length is 2000 mm with a clear span of 1800 mm between
the two simple supports, and are loaded at mid-span with a single
concentrated load. All of the beam specimens have the same crosssection
area which is 126000 mm
2
. The beam specimens B1
through B5 had a rectangular cross section with width-to-depth, b/d,
vary from 0.77 to 1.38. Beam specimen B6 is T-shape.
The analytical program considered in this study includes
performing nonlinear finite element models using ABAQUS v6.10
program. The geometrical nonlinearity, as well as the material
nonlinearity for concrete and steel was considered in the models.
These models are performed to simulate the beams behaviour and to
extend study of the behaviour of such beams. The FE results were
compared to those obtained from the experiments and the results
agreed in a satisfactory way.
Based on the test results, analytical results and review of
literature, some conclusion and recommendation were presented