Eurasian Journal of Science and Engineering
Volume 8 Issue 3 Article 10
Size Effect on Shear Strength of RC Deep Beams Strengthened with Carbon Fiber Reinforced Polymer (CFRP)
Authors: Walat Omer Miro1 & Bahman Omer Taha2 & Kamaran S. Ismail3
1Civil Engineering Department, Faculty of Engineering, Soran University, Soran, Kurdistan Region, Iraq
2Department of Civil Engineering, Erbil Technical Engineering College, Erbil Polytechnic University, Erbil, Iraq
3Civil Engineering Department, Faculty of Engineering, Soran University, Soran, Kurdistan Region, Iraq
Abstract: When the size of a conventional reinforced concrete deep beam is increased, the shear strength of the concrete at failure decreased. This is called the “size effect.” However, there has been very little research on the size effect in reinforced concrete (RC) deep beams strengthened using carbon fiber-reinforced polymer (CFRP) u-strip. This study examines how shear strengthening with CFRP strips affects the size effect. Six RC deep beams with the same shear span depth ratio (a/d=1.5) and width (b=150mm) are tested. The investigated parameters were beam height and strengthening with CFRP. The results showed that, the shear strength of the deep beams strengthened with CFRP u-strips increased by about 12–50% in comparison to the comparable control beams. CFRP may influence the size effect of shear strengthened deep beams, as the loss in ultimate shear strength was lowered from 76% to 32% when the height was increased from 200 mm to 600 mm. In addition, the presence of CFRP increased diagonal cracking strength on unstrengthened specimens by 47%, 46.8%, and 55% for 200mm, 400mm, and 600mm specimens, respectively.
Keywords: Deep Beams, Size Effect, CFRP, Shear Strength
Published: December 21, 2022
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