Strengthening Reinforced Concrete Beams Vertically Perforated through Their Entire Depth with the Use of Steel Tubes
Received: 1 May 2025 | Revised: 11 June 2025 | Accepted: 15 June 2025 | Online: 4 July 2025
Corresponding author: Haider Abedulrudha Ghani
Abstract
For architectural reasons, it is often necessary to place openings in reinforced concrete beams, even though these openings may compromise their structural integrity. The specific openings can be vertical and are intended to accommodate essential services, such as water and sewage pipes. Therefore, the former’s effect must be carefully considered during the design of building structures to ensure their safety from collapse. The objectives of this study are to understand the effect of the vertical openings and to employ strengthening techniques. To fulfill these objectives, an experimental program was designed, which involved the casting of seven RC beams. These beams were tested as simply supported members under a symmetrically two-point applied load and were classified into four groups. These groups were divided based on the type of the vertical opening (shape, number, or strengthening techniques). Each group included two specimen types: non-strengthened reference specimens and specimens strengthened by steel tubes, in addition to the reference specimen that does not contain openings. The results indicated that the introduction of a vertical opening in the RC beam, without the application of any strengthening techniques, led to an increase in the mid-span deflection and a reduction in the ultimate load-bearing capacity when contrasted with the reference solid beam. It was found that when the opening was strengthened with a steel tube, the ultimate load increased and the mid-span deflection decreased compared to the specimens without strengthening in the same group. The presence of openings in the RC beams caused a decrease in their first flexural cracking loads. Moreover, using steel tubes to strengthen the vertical openings delayed the initial cracking compared with the unreinforced specimens.
Keywords:
reinforced concrete beam, vertical opening, steel tubeDownloads
References
H. H. Ali and A. M. I. Said, "Flexural behavior of concrete beams with horizontal and vertical openings reinforced by glass-fiber-reinforced polymer (GFRP) bars," Journal of the Mechanical Behavior of Materials, vol. 31, no. 1, pp. 407–415, Jul. 2022.
A. Y. Khadhair and A. F. Izzet, "Behavior of Reinforced Concrete Beams with Vertically Penetrated Holes across the Cross ‐ Sectional Depth," Engineering, Technology & Applied Science Research, vol. 14, no. 3, pp. 14301–14307, Jun. 2024.
H. H. Ali and A. I. Said, “Experimental Study on the Performance of Concrete Beams Including Holes Reinforced with Glass Fiber Polymer,” E3S Web of Conferences, vol. 427, 2023, Art. no. 02010.
Guide to Simplified Design for Reinforced Concrete Buildings, ACI 314R-16, American Concrete Institute, Farmington Hills, MI, 2016.
A. M. Morsy and A. M. Barima, "Behavior of R.C. Beams with Openings using Different Strengthening Techniques," International Journal of Sciences: Basic and Applied Research, vol. 46, no. 1, pp. 195–219, 2019.
L. M. Olanitori and T. O. Tifase, "Effect of small transverse service holes on shear strength of reinforced concrete slender beams," Journal of Applied Sciences and Environmental Management, vol. 23, no. 3, Apr. 2019, Art. no. 539.
S. C. Chin and S. I. Doh, "Behaviour of Reinforced Concrete Deep Beams with Openings in the Shear Zones," Journal of Engineering and Technology, vol. 6, no. 1, pp. 60–71, Jun. 2015.
J. H. Ling, J. T. S. Ngu, Y. T. Lim, W. K. Leong, and H. T. Sia, "Experimental Study of RC Hollow Beams with Embedded PVC Pipes," Journal of Advanced Civil and Environmental Engineering, vol. 5, no. 1, Apr. 2022, Art. no. 11.
A. H. Aziz and A. E. Ajeel, "Effect of Existing Flange Openings and Cold Joints in Strength of RC T-Beams," Journal of Engineering, vol. 16, no. 01, pp. 4535–4546, Apr. 2010.
R. J. C. Silva, M. B. S. Muniz, É. M. F. Lima, F. E. S. D. Silva Júnior, and C. V. D. S. Araújo, "Experimental analysis of reinforced concrete beams strengthened with steel bars and epoxy structural adhesive," Revista ALCONPAT, vol. 9, no. 1, pp. 65–78, Dec. 2018.
A. S. Hamzah and A. Y. Ali, "Shear behavior of reinforced concrete beams with vertical and transverse openings," Test Engineering and Management.
Standard Specification for Deformed and Plain Billet-Steel Bars for Concrete, ASTM-A615/A615M-20, ASTM International, West Conshohocken, Pennsylvania, 2020.
Standard Specification for Concrete Aggregates, ASTM-C33-C33M-18, ASTM International, West Conshohocken, Pennsylvania, 2018.
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Copyright (c) 2025 Haider Abedulrudha Ghani, Amer F. Izzet
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