الفهرس 
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Abstract
Brittle failure always prone to shear. Therefore, researches been dedicated to reach for ductile response prior failure. Different ways for improving the ductility by installing helical or ties confinement in the compression zone were introduced. The present study discusses the shear strength and behavior of reinforced concrete beams with additional stirrups in the compression zone. Seven reinforced concrete beams, 150 mm (width) x 300 mm (depth) x 3400 mm (length) with tension steel ratio 1.5% were tested under four points static load test. The additional stirrups consisted of 6 mm diameter with yield stress of 321 N/mm2.The tested beams were identical except for additional stirrups spacing and shapes (short links and helical stirrup). Comparison with some building codes is presented. A numerical model based on the finite element method was used to represent the behavior of three beams from the experimental program using a computer package ” ABAQUS” to obtain the numerical solution for different parameters, such as deflection, ultimate load, steel strains, crack patterns and concrete strains. The study revealed that, the presence of the additional links with the vertical stirrups exhibits small effects to the enhancement to the shear strength by 8% to 14% higher. All beams failed in shear failure. The beam provided with the helical links in addition to the vertical stirrups recorded the highest shear strength by 22% higher than the control beam. The ultimate load of beam with only short links replacing the regular stirrups was only 11 % lesser than that of the control beam. Although the additional links did not influence the deflection of the beams, it affected the failure ductility. The strength predicted for the control beam by the Eurocode was the most conservative with predicted shear strength higher by 139% than the experimental results followed by the ECP code by 83%. The numerical results for the control beam were higher than the experimental results. Longitudinal steel strain did not yield in both the experimental and FE beams.