Structural Engineering and Mechanics

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Theoretical analysis of stress-strain behavior of multi-layer RC beams under flexure

  • Ertekin Oztekin (Civil Engineering Department, Faculty of Engineering and Natural Sciences, Gumushane University)
  • Received : 2022.12.26
  • Accepted : 2024.05.23
  • Published : 2024.06.10
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Abstract

In this study, obtaining theoretical stress-strain curves and determining the parameters defining the equivalent rectangular stress block were aimed for 3 and 4-layered rectangular Reinforced Concrete (RC) cross-sections subjected to flexure. For these aims, the analytical stress-strain model proposed by Hognestad was chosen for the concrete grades (20 MPa≤fck≤60 MPa) used in this study. The tensile strength of the concrete was neglected and the thickness of the concrete layers in the compression zone of the concrete cross-section was taken as equal. In addition, while concrete strength was kept constant within each layer, concrete strengths belonging to separate layers were increased from the neutral axis towards the outer face of the compression zone of the concrete cross-section. After the equivalent rectangular stress block parameters were determined by numerical iterations, variations of these parameters depending on concrete strength in layers and layer numbers were obtained. Finally, some analytical equations have been proposed to predict the equivalent stress block parameters for the 3 and 4-layered RC cross-sections and validities of these proposed equations were shown by different metrics in this study.

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References

  1. ACI 318 (2019), Building Code Requirements for Structural Concrete and Commentary, American Concrete Institute, Michigan, USA.
  2. Ali, O.K., Al-Hadithi, A.I. and Noaman, A.T. (2022), "Flexural performance of layered PET fiber reinforced concrete beams", Struct., 35, 55-67. https://doi.org/10.1016/j.istruc.2021.11.007.
  3. Butean, C. and Heghes, B. (2020), "Flexure behavior of a two-layer reinforced concrete beam", Procedia Manuf., 46, 110-115. https://doi.org/10.1016/j.promfg.2020.03.017.
  4. CSA (2004), Design of Concrete Structures, Canadian Standards Association, Mississauga, Canada.
  5. Deng, M., Zhang, M., Ma, F., Li, F. and Sun, H. (2021), "Flexural strengthening of over-reinforced concrete beams with highly ductile fiber-reinforced concrete layer", Eng. Struct., 231, 111725. https://doi.org/10.1016/j.engstruct.2020.111725.
  6. Eurocode 2 (2004), Design of Concrete Structures-Part 1-1: General Rules and Rules for Buildings, British Standard Institution, London, UK.
  7. Korol, E., Tho, V.D. and Hoang, N.H. (2018), "Analysis the effects of lightweight concrete in the middle layer of multi-layered reinforced concrete structures on the stress-strain state using the finite element method", MATEC Web Conf., 196, 02022. https://doi.org/10.1051/matecconf/201819602022.
  8. Korol, E.A. and Tho, V.D. (2020), "Bond strength between concrete layers of three-layer concrete structures", IOP Conf. Ser.: Mater. Sci. Eng., 775(1), 012115. https://doi.org/10.1088/1757-899X/775/1/012115.
  9. Kumar, P. (2006), "Effect of strain ratio variation on equivalent stress block parameters for normal weight high strength concrete", Comput. Concrete, 3(1), 17-28. https://doi.org/10.12989/cac.2006.3.1.017.
  10. Lee, D.H., Jeon, J., Jeong, M. and Kong, J. (2011), "Prediction of equivalent stress block parameters for high strength concrete", KSCE J. Civil Environ. Eng. Res., 31(3A), 227-234. https://doi.org/10.12652/ksce.2011.31.3A.227.
  11. Leung, C.K., Cheung, Y.N. and Zhang, J. (2007), "Fatigue enhancement of concrete beam with ECC layer", Cement Concrete Res., 37(5), 743-750. https://doi.org/10.1016/j.cemconres.2007.01.015.
  12. Liu, W., Xu, S. and Li, Q. (2013), "Flexural behavior of UHTCC-layered concrete composite beam subjected to static and fatigue loads", Fatig. Fract. Eng. Mater. Struct., 36(8), 738-749. https://doi.org/10.1111/ffe.12040.
  13. Lusis, V., Kononova, O., Macanovskis, A., Stonys, R., Lasenko, I. and Krasnikovs, A. (2021), "Experimental investigation and modelling of the layered concrete with different concentration of short fibers in the layers", Fiber., 9(12), 76. https://doi.org/10.3390/fib9120076.
  14. Murali, G. and Ramprasad, K. (2018), "A feasibility of enhancing the impact strength of novel layered two stage fibrous concrete slabs", Eng. Struct., 175, 41-49. https://doi.org/10.1016/j.engstruct.2018.08.034.
  15. Murali, G., Prasad, N., Klyuev, S., Fediuk, R., Abid, S.R., Amran, M. and Vatin, N. (2021), "Impact resistance of functionally layered two-stage fibrous concrete", Fiber., 9(12), 88. https://doi.org/10.3390/fib9120088.
  16. Nematzadeh, M. and Fallah-Valukolaee, S. (2021), "Experimental and analytical investigation on structural behavior of two-layer fiber-reinforced concrete beams reinforced with steel and GFRP rebars", Constr. Build. Mater., 273, 121933. https://doi.org/10.1016/j.conbuildmat.2020.121933.
  17. Nes, L.G. and Overli, J.A. (2016), "Structural behaviour of layered beams with fibre-reinforced LWAC and normal density concrete", Mater. Struct., 49(1), 689-703. https://doi.org/10.1617/s11527-015-0530-9.
  18. NZS 3101 (2006), Concrete Structures Standard, Part 1-The Design of Concrete Structure, Concrete Design Committee, Wellington, New Zealand.
  19. Oztekin, E., Pul, S. and Husem, M. (2003), "Determination of rectangular stress block parameters for high performance concrete", Eng. Struct., 25(3), 371-376. https://doi.org/10.1016/S0141-0296(02)00172-4.
  20. Park, K., Paulino, G.H. and Roesler, J. (2010), "Cohesive fracture model for functionally graded fiber reinforced concrete", Cement Concrete Res., 40(6), 956-965. https://doi.org/10.1016/j.cemconres.2010.02.004.
  21. Pratama, M.M.A., Suhud, R.K., Puspitasari, P., Kusuma, F.I. and Putra, A.B.N.R. (2019), "Finite element analysis of the bending moment-curvature of the double-layered graded concrete beam", Mater. Sci. Eng., 494(1), 012064. https://doi.org/10.1088/1757-899X/494/1/012064.
  22. Shang, J., Zhao, K., Zhang, P., Guo, W. and Zhao, T. (2021), "Flexural behavior of plain concrete beams containing strain hardening cementitious composite layers with High-Volume fly ash", Constr. Build. Mater., 286, 122867. https://doi.org/10.1016/j.conbuildmat.2021.122867.
  23. TS 500 (2000), Requirements for Design and Construction of Reinforced Concrete Structures, Turkish Standards Institution, Ankara, Turkiye.
  24. Wee, T.H., Chin, M.S. and Mansur, M.A. (1996), "Stress-strain relationship of high-strength concrete in compression", J. Mater. Civil Eng., 8(2), 70-76. https://doi.org/10.1061/(ASCE)0899-1561(1996)8:2(70).
  25. Yuan, F. and Wu, Y.F. (2019), "Analytical method for derivation of stress block parameters for flexural design of FRP reinforced concrete members", Compos. Struct., 229, 111459. https://doi.org/10.1016/j.compstruct.2019.111459.
  26. Yun, H.D. (2013), "Flexural behavior and crack-damage mitigation of plain concrete beam with a strain-hardening cement composite (SHCC) layer at tensile region", Compos. Part B: Eng., 45(1), 377-387. https://doi.org/10.1016/j.compositesb.2012.05.053.
  27. Zhang, J., Leung, C.K. and Cheung, Y.N. (2006), "Flexural performance of layered ECC-concrete composite beam", Compos. Sci. Technol., 66(11-12), 1501-1512. https://doi.org/10.1016/j.compscitech.2005.11.024.
  28. Zhang, J., Wang, Z., Ju, X. and Shi, Z. (2014), "Simulation of flexural performance of layered ECC-concrete composite beam with fracture mechanics model", Eng. Fract. Mech., 131, 419-438. https://doi.org/10.1016/j.engfracmech.2014.08.016.