Effect of Confining Method on the Ductility of Over-Reinforced Concrete Beams

Ahmed, M. M.; Farghal, O. A.; Nagah, A. K.; Haridy, A. A.

doi:10.21608/jesaun.2007.112873

Effect of Confining Method on the Ductility of Over-Reinforced Concrete Beams

Document Type : Research Paper

Authors

¹ Ass. Prof. Dr of Civil Eng. Faculty of Eng. Assiut University, Assiut, Egypt.

² Lect. Dr of Civil Eng. Faculty of Eng. Al-Azhar University, Qena, Egypt.

³ Demonstrator in Civil Eng. Faculty of Eng. Al-Azhar University, Qena, Egypt.

10.21608/jesaun.2007.112873

Abstract

Most design codes limit the amount of tensile reinforcement in beams to avoid the brittle failure. However, sometimes a high percentage of steel reinforcement is used in order to minimize structural depth and still provide adequate stiffness. The objective of this work is to investigate and evaluate the methods of improving the behavior of over-reinforced beams. The effect of different types of techniques on the enhancement of strength and ductility of such beams was presented. An experimental and theoretical study of the behavior of fourteen over-reinforced, either internally confined or externally plated C. beams with 240 cm length and a cross-section of 15 x 23cm were carried out. Variables such as helix pitch, helix diameter, concrete compressive strength, longitudinal reinforcement ratio and confining with steel plate were considered. The results were discussed, analyzed and compared with those obtained theoretically. The results indicated the contribution of proposed techniques to the structural ductility for improving behaviour of such over-reinforced concrete beams. Finally some valuable conclusions and recommendations were given.

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