Shear Behavior of Small-Scale Continuous Hidden Beams Using Tied and Spiral Stirrups
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Hidden beams in reinforced concrete (RC) structures are widely used to meet architectural requirements; however, their reduced effective depth limits shear capacity. This study investigates the shear behavior of hidden beams reinforced with innovative rectangular staggered continuous spiral stirrups, addressing the absence of design guidelines for such reinforcement systems. Nine one-eighth-scale continuous beams were tested under two-point loading, with mortar used to reduce scale effects. The influence of the number, geometry, and configuration of spiral reinforcement was investigated. Both conventional and spiral stirrups significantly improved shear performance compared to the reference beam without transverse reinforcement (HB9-No). Beams with normal stirrups (HB1-N20, HB2-N30, HB3-N40, HB4-N50) increased shear capacity by 115%, 82%, 23%, and 4%, while spiral stirrup beams (HB1-S20, HB2-S30, HB3-S40, HB4-S50) achieved corresponding increases of 174%, 144%, 73%, and 27%, respectively. Overall, spiral reinforcement enhanced shear capacity and energy dissipation by approximately 30% and 46%, respectively, compared with conventional stirrups. Prototype capacities estimated using scaling relationships were compared with international design codes, which were found to be conservative. The findings demonstrate the effectiveness of spiral stirrups in improving shear strength and ductility and emphasize the need to include their contribution in future shear design equations for hidden beams.
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[1] Meynagh, M. M., Yasouj, S. E. M., & Marsono, A. K. B. (2013). Reinforced Concrete Beam’s Contribution on Sustainable Buildings. Engineering Research & Technology, 2(4), 138-143.
[2] Conforti, A., Minelli, F., Tinini, A., & Plizzari, G. A. (2015). Influence of polypropylene fibre reinforcement and width-to-effective depth ratio in wide-shallow beams. Engineering Structures, 88, 12–21. doi:10.1016/j.engstruct.2015.01.037.
[3] Mohammed, S. D., Salman, H. M., Ibrahim, T. H., Oukaili, N. K., & Allawi, A. A. (2025). On the Impact of Lacing Reinforcement Arrangement on Reinforced Concrete Deep Beams Performance. Civil Engineering Journal, 11(2), 726–745. doi:10.28991/CEJ-2025-011-02-019.
[4] Lubell, A. S., Bentz, E. C., & Collins, M. P. (2009). Shear reinforcement spacing in wide members. ACI Structural Journal, 106(2), 205–214. doi:10.14359/56359.
[5] Azimi, M., Bagherpourhamedani, A., Tahir, M. M., Sam, A. R. B. M., & Ma, C. K. (2016). Evaluation of new spiral shear reinforcement pattern for reinforced concrete joints subjected to cyclic loading. Advances in Structural Engineering, 19(5), 730–745. doi:10.1177/1369433216630371.
[6] Piscesa, B., Attard, M. M., Samani, A. K., & Tangaramvong, S. (2017). Plasticity constitutive model for stress-strain relationship of confined concrete. ACI Materials Journal, 114(2), 361–371. doi:10.14359/51689428.
[7] Shatarat, N., Katkhuda, H., Abdel-Jaber, M., & Alqam, M. (2016). Experimental investigation of reinforced concrete beams with spiral reinforcement in shear. Construction and Building Materials, 125, 585–594. doi:10.1016/j.conbuildmat.2016.08.070.
[8] Joshy, V., & Faisal, K. M. (2017). Experimental study on the behaviour of spirally reinforced SCC beams. International Journal of Engineering Research and General Science, 5(3), 96-105.
[9] Iyengar, K. T. S. R., Desayi, P., & Reddy, K. N. (1972). Confined concrete-Its application in R.C. beams and frames. Building Science, 7(2), 105–120. doi:10.1016/0007-3628(72)90047-3.
[10] Mander, J. B., Priestley, M. J. N., & Park, R. (1988). Theoretical Stress-Strain Model for Confined Concrete. Journal of Structural Engineering, 114(8), 1804–1826. doi:10.1061/(asce)0733-9445(1988)114:8(1804).
[11] Hu, B., & Wu, Y. F. (2018). Effect of shear span-to-depth ratio on shear strength components of RC beams. Engineering Structures, 168, 770–783. doi:10.1016/j.engstruct.2018.05.017.
[12] Meghana, M. B., & Vedic, N. (2018). Shear Capacity of RC Beams with Different Patterns of Spiral Reinforcements. International Journal of Engineering Research & Technology, 6(6), 2278–0181. doi:10.17577/IJERTCONV6IS06017.
[13] Kumar, T. R. S., & Sreevalli, I. Y. (2020). Numerical study on flexural performance of RC beam with various confinement pattern. Engineering Research Express, 2(1), 15016. doi:10.1088/2631-8695/ab68a3.
[14] Dewi, S. H., Thamrin, R., Zaidir, & Taufik. (2020). Effect of stirrup type on shear capacity of reinforced concrete members with circular cross section. E3S Web of Conferences, 156, 05022. doi:10.1051/e3sconf/202015605022.
[15] Karayannis, C. G., & Chalioris, C. E. (2013). Shear tests of reinforced concrete beams with continuous rectangular spiral reinforcement. Construction and Building Materials, 46, 86–97. doi:10.1016/j.conbuildmat.2013.04.023.
[16] Jaafar, K. (2008). Shear behaviour of reinforced concrete beams with confinement near plastic hinges. Magazine of Concrete Research, 60(9), 665–672. doi:10.1680/macr.2008.60.9.665.
[17] Jaafar, K. (2013). Utilising confinement reinforcement for shear resistance in reinforced concrete structures. Magazine of Concrete Research, 65(4), 220–233. doi:10.1680/macr.12.00061.
[18] Mohamed, H. A. (2018). Improvement in the Ductility of Over-reinforced NSC and HSC Beams by Confining the Compression Zone. Structures, 16, 129–136. doi:10.1016/j.istruc.2018.09.005.
[19] Tee, H. H., Al-Sanjery, K., & Chiang, J. C. L. (2018). Behaviour of over-reinforced concrete beams with double helix and double square confinements related to ultimate bending and shear strength. Journal of Physical Science, 29, 77–98. doi:10.21315/jps2018.29.s2.7.
[20] Abdelkhaliq, N. M., & Hilal, A. M. (2017). Experimental and Analytical Study of Confined Compression Zone on Capacity of Reinforced Concrete Beams. IOSR Journal of Mechanical and Civil Engineering, 14(01), 01–07. doi:10.9790/1684-1401070107.
[21] Li, W., Huang, W., Kong, Z., Fan, W., & Zhang, K. (2025). Shear behavior of SFRC beams reinforced with FRP stirrups: Experimental and analytical investigations. Steel and Composite Structures, 56(1), 83–98. doi:10.12989/scs.2025.56.1.083.
[22] Yu, Q., Yang, Y., Lin, Q., & Yang, D. (2024). Experimental Study on the Shear Behavior of HTRCS-Reinforced Concrete Beams. Buildings, 14(10), 3209. doi:10.3390/buildings14103209.
[23] He, J., Liu, J., Li, N., Li, J., & Fu, B. (2025). Shear behavior of concrete beams reinforced with GFRP-steel hybrid stirrups. Construction and Building Materials, 472, 140882. doi:10.1016/j.conbuildmat.2025.140882.
[24] Abdullah, M., Nakamura, H., & Miura, T. (2024). Experimental investigation on influence of vertical stirrup legs to shear failure behavior in RC beams. Developments in the Built Environment, 18. doi:10.1016/j.dibe.2024.100451.
[25] Ghalla, M., Bahrami, A., Mlybari, E., & Badawi, M. (2025). Shear behavior of reinforced concrete beams strengthened utilizing optimized external post-tensioning techniques. Frontiers of Structural and Civil Engineering, 19(6), 961–979. doi:10.1007/s11709-025-1185-4.
[26] Gouda, M. G., Mostafa, I. T., Mohamed, H. M., Sherif, A., & Agamy, M. H. (2025). Understanding the impact of spiral reinforcement on GFRP-RC beams under combined shear and torsion loading. Engineering Structures, 332, 120019. doi:10.1016/j.engstruct.2025.120019.
[27] Chen, C., Fang, H., Lim, Y. M., & Choo, B. (2025). Shear behavior of novel GFRP stirrup and GFRP bar reinforced circular concrete members. Engineering Structures, 345. doi:10.1016/j.engstruct.2025.121509.
[28] Elansary, A. A., Elnazlawy, Y. Y., & Abdalla, H. A. (2022). Shear behaviour of concrete wide beams with spiral lateral reinforcement. Australian Journal of Civil Engineering, 20(1), 174–194. doi:10.1080/14488353.2021.1942405.
[29] Youssef, A., Mawaad, S., & Salem, H. (2024). Shear capacity of miniature beams with continuous staggered spiral stirrups. Journal of Engineering and Applied Science, 71(1), 53. doi:10.1186/s44147-024-00380-3.
[30] Mahmoud, S., Youssef, A., & Salem, H. (2022). Enhanced Torsion Mechanism of Small-Scale Reinforced Concrete Beams with Spiral Transverse Reinforcement. Civil Engineering Journal (Iran), 8(11), 2640–2660. doi:10.28991/CEJ-2022-08-11-019.
[31] Elbasha, N. M., & Hadi, M. N. S. (2005). Effect of helical pitch and tensile reinforcement ratio on the concrete cover spalling off load and ductility of HSC beams. Proceedings of the Australian Structural Engineering Conference 2005, 2005, 54–64.
[32] Ziara, M. M., Haldane, D., & Hood, S. (2000). Proposed changes to flexural design in BS 8110 to allow over-reinforced sections to fail in a ductile manner. Magazine of Concrete Research, 52(6), 443–454. doi:10.1680/macr.2000.52.6.443.
[33] Mosley, W. H., Bungey, J., & Hulse, R. (1999). Reinforced Concrete Design Handbook. Palgrave Macmillan, London, United Kingdom.
[34] Ahmed, M. M., Farghal, O. A., Nagah, A. K., & Haridy, A. A. (2007). Effect of Confining Method on the Ductility of Over-Reinforced Concrete Beams. JES. Journal of Engineering Sciences, 35(3), 617–633. doi:10.21608/jesaun.2007.112873.
[35] Priastiwi, Y. A., Imran, I., Nuroji, & Hidayat, A. (2014). Behavior of ductile beam with addition confinement in compression zone. Procedia Engineering, 95, 132–138. doi:10.1016/j.proeng.2014.12.172.
[36] Priastiwi, Y. A., Imran, I., & Nuroji. (2015). The effect of different shapes of confinement in compression zone on beam’s ductility subjected to monotonic loading. Procedia Engineering, 125, 918–924. doi:10.1016/j.proeng.2015.11.098.
[37] Jang, I.-Y., Park, H.-G., Kim, Y.-G., Kim, S.-S., & Kim, J.-H. (2009). Flexural Behavior of High-Strength Concrete Beams Confined with Stirrups in Pure Bending Zone. International Journal of Concrete Structures and Materials, 3(1), 39–45. doi:10.4334/ijcsm.2009.3.1.039.
[38] Ahmed, A., Mohammed, A. M. Y., & Maekawa, K. (2021). Correlation of High Cycle Fatigue Behavior of Circular and Square Reinforced Concrete Columns Subjected to Shear Controlled Cyclic Loading. KSCE Journal of Civil Engineering, 25(5), 1755–1764. doi:10.1007/s12205-021-0850-y.
[39] Mohammed, A. M. Y., Ali, A. R. M., & Abdalla, H. A. (2021). Non-linear behavior of low strength RC beams strengthened with CFRP sheets. Civil Engineering Journal (Iran), 7(3), 518–530. doi:10.28991/cej-2021-03091670.
[40] Mohammed, A. M. Y., & Maekawa, K. (2012). Global and local impacts of soil confinement on RC pile nonlinearity. Journal of Advanced Concrete Technology, 10(11), 375–388. doi:10.3151/jact.10.375.
[41] Abdelaal, A., & Youssef, A. (2023). Experimental investigation on corroded and non-corroded RC tunnels under different loading conditions. Journal of Engineering and Applied Science, 70(1), 146. doi:10.1186/s44147-023-00306-5.
[42] Youssef, A., Hegazy, M., & Mostafa, H. (2023). Performance of Isolated Footing with Several Corrosion Levels under Axial Loading. Civil Engineering Journal (Iran), 9(6), 1437–1455. doi:10.28991/CEJ-2023-09-06-011.
[43] ACI 318-19. (2019). Building Code Requirements for Structural Concrete. American Concrete Institute (ACI), Farmington Hills. United States.
[44] EN 1992-2. (2015). Design of concrete structures - Part 1-1: General rules and rules for buildings. European Committee for Standardization, Brussels, Belgium.
[45] JSCE. (2007). Standard specifications for concrete structures. Japan Society of Civil Engineers (JSCE), Tokyo, Japan.
[46] BS 8110-1:1997. (1997). Structural use of concrete: Code of practice for design and construction (BS 8110-1:1997). British Standards Institution (BSI), London, United Kingdom.
[47] CSA A23.3-04. (2004). Design of concrete structures. Canadian Standards Association (CSA), Toronto, Canada.
[48] ECP 203. (2020). The Egyptian Code for Design and Construction of Concrete Structures. Housing and Building Research Center, Giza, Egypt.
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