Limiting Reinforcement Ratios for Hybrid GFRP/Steel Reinforced Concrete Beams
Keywords:GFRP, hybrid reinforcement, reinforcement ratio
In this work, a theoretical approach is proposed for estimating the minimum and maximum reinforcement ratios for hybrid glass fiber reinforced polymer (GFRP)/steel-reinforced concrete beams to prevent sudden and brittle failure as well as the compression failure of concrete before the tension failure of reinforcements. Equilibrium equations were used to develop a method for determining the minimum hybrid GFRP/steel reinforcement ratio. A method for determining the maximum hybrid GFRP/steel reinforcement ratio was also developed based on the equilibrium of forces of the balanced failure mode. For estimating the load-carrying capacity of concrete beams reinforced with hybrid GFRP/steel, less than the minimum and more than the maximum reinforcement ratio is recommended. Comparisons between the proposed expressions, experimental data, and available test results in the literature shows good agreement between the theoretical and experimental data, with a maximum discrepancy of 7%.
C. Jeetendra, K. Suresh, and A. Hussain, “Application of FRP in Concrete Structures,” International Journal of Engineering Associates, vol. 4, pp. 50-51, January 2015.
S. B. Singh, Analysis and Design of FRP Reinforced Concrete Structures, New Delhi: McGraw-Hill Education, 2015.
L. Ade and P. Purwanelson, “Axial and Flexural Strength of Square RC Columns with No-rounded Corners Wrapped with CFRP under Eccentric Loading,” International Journal of Engineering and Technology Innovation, vol. 8, no. 1, pp. 38, January 2018.
A. E. Uğur, A. Ünal, B. A. Akgöbek, M. Kamanlı, and S. Cengiz, “Use of GFRP Bar in Civil Engineering,” 4th International Symposium on Innovative Approaches in Engineering and Natural Sciences (ISAS WINTER-2019), July 2019, pp. 95-100.
B. Benmokrane and R. Masmoudi, “Flexural Response of Concrete Beams Reinforced with FRP Reinforcing Bars,” Structural Journal, vol. 93, no. 1, pp. 46-55, January 1996.
M. Konsta-Gdoutos and C. Karayannis, “Flexural Behaviour of Concrete Beams Reinforced with FRP Bars,” Advanced Composites Letters, vol. 7, no. 5, pp. 133-138, January 1998.
C. Barris, L. Torres, J. Comas, and C. Miàs, “Cracking and Deflections in GFRP RC Beams: An Experimental Study,” Composites Part B: Engineering, vol. 55, pp. 580-590, December 2013.
A. Ramachandra Murthy, D. M. Pukazhendhi, S. Vishnuvardhan, M. Saravanan, and P. Gandhi, “Performance of Concrete Beams Reinforced with GFRP Bars under Monotonic Loading,” Structures, vol. 27, pp. 1274-1288, October 2020.
M. Aiello and L. Ombres, “Structural Performances of Concrete Beams with Hybrid (Fiber-Reinforced Polymer-Steel) Reinforcements,” Journal of Composites for Construction, vol. 6, no. 2, pp. 133-140, January 2002.
H. Y. Leung and R. V. Balendran, “Flexural Behaviour of Concrete Beams Internally Reinforced with GFRP Rods and Steel Rebars,” Structural Survey, vol. 21, no. 4, pp. 146-157, October 2003.
W. Qu, X. Zhang, and H. Huang, “Flexural Behavior of Concrete Beams Reinforced with Hybrid (GFRP and Steel) Bars,” Journal of Composites for Construction, vol. 13, no. 5, pp. 350-359, March 2009.
X. Ruan, C. Lu, K. Xu, G. Xuan, and M. Ni, “Flexural Behavior and Serviceability of Concrete Beams Hybrid-Reinforced with GFRP Bars and Steel Bars,” Composite Structures, vol. 235, p. 111772, March 2020.
Y. Yang, Z. Y. Sun, G. Wu, D. F. Cao, and Z. Q. Zhang, “Flexural Capacity and Design of Hybrid FRP-Steel-Reinforced Concrete Beams,” Advances in Structural Engineering, vol. 23, no. 7, pp. 1290-1304, December 2019.
X. Gu, Y. Dai, and J. Jiang, “Flexural Behavior Investigation of Steel-GFRP Hybrid-Reinforced Concrete Beams Based on Experimental and Numerical Methods,” Engineering Structures, vol. 206, p. 110117, March 2020.
P. D. Nguyen, V. H. Dang, and N. A. Vu, “Performance of Concrete Beams Reinforced with Various Ratios of Hybrid GFRP/Steel Bars,” Civil Engineering Journal, vol. 6, no. 9, pp. 1652-1669, September 2020.
L. Pang, W. Qu, P. Zhu, and J. Xu, “Design Propositions for Hybrid FRP-Steel Reinforced Concrete Beams,” Journal of Composites for Construction, vol. 20, no. 4, p. 04015086, December 2015.
J. Zhang, W. Ge, H. Dai, and Y. Tu, “Study on the Flexural Capacity of Concrete Beam Hybrid Reinforced with FRP Bars and Steel Bars,” 5th International Conference on FRP Composites in Civil Engineering (CICE 2010), September 2010, pp. 304-307.
B. Jia, S. Liu, X. Liu, and R. Wang, “Flexural Capacity Calculation of Hybrid Bar Reinforced Concrete Beams,” Materials Research Innovations, vol. 18, no. sup2, pp. S2-836-S2-840, May 2014.
SP 63.13330, Concrete and Reinforced Concrete Structures, General provisions, 2018.
ACI 318, Building Code Requirements for Structural Concrete, American Concrete Institute, 2019.
M. N. Hassoun and A. Al-Manaseer, Structural Concrete: Theory and Design, 7th ed. Wiley, 2020.
SP 295.1325800, Concrete Structures Reinforced with Fibre-Reinforced Polymer Bars, Design Rules, 2017.
ACI 440.1R, Guide for the Design and Construction of Structural Concrete Reinforced with FRP Bars, 2015.
A. Carpinteri, Applications of Fracture Mechanics to Reinforced Concrete, 1st ed. New York: CRC Press, 1992.
T. M. Fayyad and J. Lees, “Evaluation of a Minimum Flexural Reinforcement Ratio Using Fracture-Based Modelling,” IABSE Symposium Report, vol. 105, no. 35, pp. 1-8, September 2015.
A. Nanni, A. De Luca, and H. J. Zadeh, Reinforced Concrete with FRP Bars: Mechanics and Design, CRC Press, 2014.
Q. S. Khan, S. M. Neaz, and M. N. S. Hadi, “Tension and Compression Testing of Fibre Reinforced Polymer (FRP) Bars,” The 12th International Symposium on Fiber Reinforced Polymers for Reinforced Concrete Structures (FRPRCS-12) & The 5th Asia-Pacific Conference on Fiber Reinforced Polymers in Structures (APFIS-2015), December 2015, pp. 1-6.
J. Ožbolt and M. Bruckner, “Minimum Reinforcement Requirement for RC Beams,” European Structural Integrity Society, vol. 24, pp. 181-201, 1999.
D. Lau and H. Pam, “Experimental Study of Hybrid FRP Reinforced Concrete Beams,” Engineering Structures, vol. 32, no. 12, pp. 3857-3865, December 2010.
K. H. Tan, “Behavior of Hybrid FRP-Steel Reinforced Concrete Beams,” Third International Symposium on Non-Metallic (FRP) Reinforcement for Concrete Structures (FRPRCS-3), October 1997, pp. 487-494.
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