الفهرس 
LITERATURE REVIEWOnly 14 pages are availabe for public view
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Abstract
The main objective of the research is to investigate and evaluate the behavior of top loaded simply supported deep beams with square web openings experimentally and theoretically by using internal GFRP bars. The main used parameters are strength of concrete, opening position, horizontal and vertical web reinforcement ratios, and additional reinforcement around openings as a ratio and shape. Many codes of practice suggested different span to depth ratios to consider the beam as a deep beam. In general, simply supported beams having span to depth(a/d) ratio less than 2.5 classified as a deep beam in flexure. In the current study, all the tested specimens have span to depth ratio equal to 1.25 which is less than 2.5 to overcome the different definitions given by the various codes. A total of 10 deep beams with and without web openings were constructed and tested under two-point load. Test specimen had a cross section of 100 x 805 mm and a length of 975 mm.
All Specimens were loaded until failure. The failure mechanisms, deformation, and ultimate load of each specimen were generated and analyzed. The load-deflection curves are presented. It can be concluded that, using GFRP bars lead to reduce the ultimate capacity of tested specimens with and without web openings, while the changing of concrete compressive had a significant effect of the overall deep beam behavior.
In addition, increasing web reinforcement ratios lead to increase the ultimate capacity. Strength increased when web openings located away from the shear span region. Also, additional reinforcement around the web openings reduce the cracks number and deflection and gives failure to be gradual and slow.
This points to display a model appropriate for analyzing reinforcement concrete deep beams with square web openings theoretically by using internal GFRP-bars. A three dimensional nonlinear finite element analysis has been utilized to conduct an explanatory investigation on the general behavior of reinforced concrete deep beams. A Strut and Tie method (STM) and a finite element program (FEP) ABAQUS (2017) is used for the theoretical analysis of all tested specimens. The analysis includes nonlinear stress-strain relations of concrete in compression, concrete cracking in tension, yielding of both flexural steel reinforcement and GFRP-bars and crushing of concrete. The legitimacy of the adopted models and STM was confirmed through comparison with the experimental data available, and the arrangement has demonstrated to be acceptable. Through regression analysis, a set of statistical processes were generated to estimate the relationships between the above-mentioned dependent variable states.