Computers and Concrete

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Finite element analysis of reinforced concrete spandrel beams under combined loading

  • Ibraheem, O.F. (Department of Civil Engineering, University Sains Malaysia (USM)) ;
  • Bakar, B.H. Abu (Department of Civil Engineering, University Sains Malaysia (USM)) ;
  • Johari, I. (Department of Civil Engineering, University Sains Malaysia (USM))
  • Received : 2012.04.18
  • Accepted : 2013.07.10
  • Published : 2014.02.25
⟨ Previous Next ⟩

Abstract

A nonlinear, three-dimensional finite element analysis was conducted on six intermediate L-shaped spandrel beams using the "ANSYS Civil FEM" program. The beams were constructed and tested in the laboratory under eccentric concentrated load at mid-span to obtain a combined loading case: torsion, bending, and shear. The reinforcement case parameters were as follows: without reinforcement, with longitudinal reinforcement only, and reinforced with steel bars and stirrups. All beams were tested under two different combined loading conditions: T/V = 545 mm (high eccentricity) and T/V = 145 mm (low eccentricity). The failure of the plain beams was brittle, and the addition of longitudinal steel bars increased beam strength, particularly under low eccentricity. Transverse reinforcement significantly affected the strength at high eccentricities, that is, at high torque. A program can predict accurately the behavior of these beams under different reinforcement cases, as well as under different ratios of combined loadings. The ANSYS model accurately predicted the loads and deflections for various types of reinforcements in spandrel beams, and captured the critical crack regions of these beams.

Keywords

References

  1. ACI 318-05 (2005), American concrete institute, Building code requirements for structural concrete and commentary, Michigan.
  2. Ameli, M., Ronagh, H.R. and Dux, P.F. (2007), "Behavior of FRP strengthened reinforced concrete beams under torsion", J. Compos. Constr., 11(2), 192-200. https://doi.org/10.1061/(ASCE)1090-0268(2007)11:2(192)
  3. ANSYS 12.0 Program, "ANSYS Manual help," Version 12, 2009.
  4. Bernardo, L.F.A. and Lopes, S.M.R. (2008), "Behavior of concrete beams under torsion: NSC plain and hollow beams", Mater. Struct., 41, 1143-1167. https://doi.org/10.1617/s11527-007-9315-0
  5. Bernardo, L.F.A., Andrade, J.M.A. and Lopes, S.M.R. (2012), "Modified variable angle truss-model for torsion in reinforced concrete beams", Mater. Struct., 45, 1877-1902. https://doi.org/10.1617/s11527-012-9876-4
  6. Bhatti, M.A. and Almughrabi, A. (1996), "Refined model to estimate torsional strength of concrete beams", ACI Struct. J., 93(5), 614-622.
  7. Greene, G.J. and Belarbi, A. (2009), "Model for reinforced concrete members under torsion, bending, and shear. I: theory", J. Eng. Mech.-ASCE, 135(9), 961-969. https://doi.org/10.1061/(ASCE)0733-9399(2009)135:9(961)
  8. Gregori, J.N., Sosa, P.M., Prada, M.A. and Filippou, F.C. (2007), "A 3D numerical model for reinforced and prestressedconcrete elements subjected to combined axial, bending, shear and torsion loading", Eng. Struct., 29, 3404-3419. https://doi.org/10.1016/j.engstruct.2007.09.001
  9. Jing, M. and Grunberg, J. (2006), "Mechanical analysis of reinforced concrete box beam strengthened with carbon fiber sheets under combined actions", Compos. Struct., 73, 488-494. https://doi.org/10.1016/j.compstruct.2005.02.020
  10. Kachlakev, D., Miller, T. and Yim, S. (2001), Finite Element Modeling of Reinforced Concrete Structures Strengthened with Frplaminates, Oregon Dept. of Transp., USA, Res. Group, Final Report SPR 316.
  11. Karayannis, C.G. (2000), "Smeared crack analysis for plain concrete in torsion", J. Struct. Eng-ASCE, 126 (6), 638-645. https://doi.org/10.1061/(ASCE)0733-9445(2000)126:6(638)
  12. Lopes, A.V. and Lopes, S.M.R. (2012), "Importance of a rigorous evaluation of the cracking moment in RC beams and slabs", Comput. Concr., 9(4), 275-291. https://doi.org/10.12989/cac.2012.9.4.275
  13. Madenci, E. and Guven, I. (2006), The Finite Element Method and Applications in Engineering Using ANSYS, Springer Science + Business Media, New York, USA.
  14. Mahmood, N.M. (2007), "Nonlinear analysis of reinforced concrete beams under pure torsion", J. Appl. Sci., 7(22), 3524-3529. https://doi.org/10.3923/jas.2007.3524.3529
  15. Ngo, D. and Scordelis, A.C. (1967), "Finite element analysis of reinforced concrete beams", Proceedings, ACI J., 64(3), Mar.
  16. Nilson, A.H., Darwin, D. and Dolan, C.W. (2004), Design of Concrete Structures, the McGraw-Hill Companies, New York, USA.
  17. Rao, T.D. and Seshu, D.R. (2006), "Torsional response of fibrous reinforced concrete members: effect of single type of reinforcement", Constr. Build Mater., 20,187-192. https://doi.org/10.1016/j.conbuildmat.2005.01.017
  18. Santhakumar, R., Dhanaraj, R. and Chandrassekaran, E. (2007), "Behavior of retrofitted reinforced concrete beams under combined bending and torsion: anumerical study", Electron. J. Struct. Eng., 7, 1-7.
  19. Wang, W. and Hsu, C.T. (1997), "Limit analysis of reinforced concrete beams subjected to pure torsion", J. Struct. Eng.-ASCE, 123(1), 86-94. https://doi.org/10.1061/(ASCE)0733-9445(1997)123:1(86)

Cited by

  1. Computer based estimation of backbone curves for hysteretic Response of reinforced concrete columns under static cyclic lateral loads vol.14, pp.2, 2014, https://doi.org/10.12989/cac.2014.14.2.193