Structural Engineering and Mechanics

Techno-Press (테크노프레스)
권호 표지
DOI QR코드

DOI QR Code

Elastic distortional buckling of tapered composite beams

  • Bradford, M.A. (Department of Structural Engineering, School of Civil Engineering, The University of New South Wales) ;
  • Ronagh, H.R. (Department of Structural Engineering, School of Civil Engineering, The University of New South Wales)
  • Published : 1997.05.25
⟨ Previous Next ⟩

Abstract

The overall buckling mode in a composite steel-concrete beam over an internal support is necessarily lateral-distortional, in which the bottom compressive range displaces laterally and twists, since the top flange is restrained by the nearly rigid concrete slab. An efficient finite element method is used to study elastic lateral-distortional buckling in composite beams whose steel portion is tapered. The simplified model for a continuous beam that is presented herein is a fixed ended cantilever whose steel portion is tapered, and is subjected to moment gradient. This is intended to give an insight into distortion in a continuous beam that occurs in the negative bending region, and the differences between the cantilever representation and the continuous beam are highlighted. An eigenproblem is established, and the buckling modes and loads are determined in the elastic range of structural response. It is found from the finite element study that the buckling moment may be enhanced significantly by using a vertical stiffener in the region where the lateral movement of the bottom range is greatest. This enhancement is quantified in the paper.

Keywords

References

  1. Akay, H.U., Johnson, C.P. and Will, K.M. (1977), "Lateral and local buckling of beams and frames", Journal of the Structural Division, ASCE, 103(ST9), 1821-1832.
  2. Boswell, L.F. (1993), "The distortional lateral buckling of haunched composite beams", 13th Australasian Conference on the Mechanics of Structures and Materials, University of Wollongong, Autralia, 89-95.
  3. Boswell, L.F. and Li, Q. (1992), "Inelastic buckling of haunched composite beams", In Structural Integrity and Assessment, (P. Stanley ed.), Elsevier Applied Science, London, 413-423.
  4. Bradford, M.A. (1989), "Buckling strength of partially restrained I-beams", Journal of Structural Engineering, ASCE, 115(5), 1272-1276. https://doi.org/10.1061/(ASCE)0733-9445(1989)115:5(1272)
  5. Bradford, M.A. (1990), "Local buckling of trough girders", Journal of Structural Engineering, ASCE, 116(6), 1594-1610. https://doi.org/10.1061/(ASCE)0733-9445(1990)116:6(1594)
  6. Bradford, M.A. (1992), "Lateral distortional buckling of steel I-section members", Journal of Constructional Steel Research, 23, 97-116. https://doi.org/10.1016/0143-974X(92)90038-G
  7. Bradford, M.A. and Gao, Z. (1992), "Distortional buckling solutioins for continuous composite beams", Journal of Structural Engineering, ASCE, 118(1), 73-89. https://doi.org/10.1061/(ASCE)0733-9445(1992)118:1(73)
  8. Bradford, M.A. and Trahair, N.S. (1983), "Lateral stability of beams on seats", Journal of Structural Engineering, ASCE.
  9. Hancock, G.J., Bradford, M.A. and Trahair, N.S. (1980), "Web distortion and flexural-torsional buckling", Journal of Structural Division, ASCE, 106(ST7), 1557-1571.
  10. Hopper, C.T. and Williams, F.W. (1977), "Mode finding in nonlinear structural eigenvalue calculations", Journal of Structural Mechanics, 5(3), 255-278. https://doi.org/10.1080/03601217708907314
  11. Lawson, R.M. and Rackham, J.W. (1989), Design of Haunced Composite Beams in Buildings, The Steel Construction Institute, Ascot, U.K., Publication No. 060.
  12. Oehlers, D.J. and Bradford, M.A. (1995), Composite Steel-Concrete Structural Members: Fundamental Behaviour, Pergamon Press, Oxford.
  13. Ronagh, H.R. andBradford, M.A. (1994), "Elastic distortional buckling of tapered I-beams", Engineering Structures, 16(2), 97-110. https://doi.org/10.1016/0141-0296(94)90035-3
  14. Ronagh, H.R. and Bradford, M.A. (1996), "A rational model for the distortioinal buckling of tapered members", Computer Methods in Applied Mechanics and Engineering, 130, 263-277. https://doi.org/10.1016/0045-7825(95)00930-2
  15. Trahair, N.S. (1993), Flexural-Torsional Buckling of Structures, Chapman and Hall, London.
  16. Trahair, N.S. and Bradford, M.A. (1991), The Behaviour and Design of Steel Structures, Chapman and Hall, London.
  17. Weston, G. and Nethercot, D.A. (1987), "Continuous composite bridge beams-stability of the steel compressive flange under hogging bebding", Proceedings, Stability of Plates and Shell Structures, ECCS, Vandepitte, 47-52.
  18. Wilkinson, J.H. (1965), The Algebraic Eigenvalue Problem, Clarendon Press, Oxford.
  19. Williams, F.W., Jemah, A.K. and Lam, D.H. (1993), "Distortional buckling curves for continuous beams", Journal of Structural Engineering, ASCE, 119(7), 2143-2149.

Cited by

  1. Finite element linear and nonlinear, static and dynamic analysis of structural elements – an addendum – A bibliography (1996‐1999) vol.17, pp.3, 2000, https://doi.org/10.1108/02644400010324893
  2. Inelastic restrained distortional buckling of continuous composite T-beams vol.65, pp.4, 2009, https://doi.org/10.1016/j.jcsr.2008.05.002