Structural Engineering and Mechanics

  • 제6권4호
  • /
  • Pages.411-425
  • /
  • 1998
  • /
  • 1225-4568(pISSN)
  • /
  • 1598-6217(eISSN)
테크노프레스 (Techno-Press)
권호 표지
DOI QR코드

DOI QR Code

New stability equation for columns in unbraced frames

  • Essa, Hesham S. (Department of Civil Engineering, Ain Shams University)
  • 발행 : 1998.06.25
⟨ 이전 논문 다음 논문 ⟩

초록

The effective length factor of a framed column may be determined by means of the alignment chart procedure. This method is based on many unrealistic assumptions, among which is that all columns have the same stiffness parameter, which is dependent on the length, axial load, and moment of inertia of the column. A new approximate method is developed for the determination of effective length factors for columns in unbraced frames. This method takes into account the effects of inelastic column behaviour, far end conditions of the restraining beams and columns, semi-rigid beam-to-column connections, and differentiated stiffness parameters of columns. This method may be implemented on a microcomputer. A numerical study was carried out to demonstrate the extent to which the involved parameters affect the K factor. The beam-to-column connection stiffness, the stiffness parameter of columns, and the far end conditions of restraining members have a significant effect on the K factor of the column under investigation. The developed method is recommended for design purposes.

키워드

참고문헌

  1. Ackroid, M.H. and Gerstle, K.H. (1983), "Elastic stability of flexibly connected frames", J. Struct. Engrg, ASCE, 109(1), 241-245. https://doi.org/10.1061/(ASCE)0733-9445(1983)109:1(241)
  2. Bridge, R.Q. and Fraser, D. (1987), "Improved G-factor method for evaluating effective lengths of columns", J. Struct. Engrg., ASCE, 113(6), 1341-1356. https://doi.org/10.1061/(ASCE)0733-9445(1987)113:6(1341)
  3. Chapius, J. and Galambos, T.V. (1982), "Restrained crooked aluminum columns", J. Struct. Div., ASCE, 108(3), 511-524.
  4. Chen, W.F. and Lui, E.M. (1991), Stability Design of Steel Frames, CRC Press.
  5. Duan, L. and Chen, W.F. (1988), "Effective length factor for columns in braced frames", J. Struct. Engrg., ASCE, 114(10), 2357-2370. https://doi.org/10.1061/(ASCE)0733-9445(1988)114:10(2357)
  6. Duan, L. and Chen, W.F. (1989), "Effective length factor for columns in unbraced frames", J. Struct. Engrg., ASCE, 115(1), 149-165. https://doi.org/10.1061/(ASCE)0733-9445(1989)115:1(149)
  7. Essa, H.S. (1997), "Stability of columns in unbraced frames", J. Struct. Engrg., ASCE, 123(7).
  8. Essa, H.S. and Hekal, S.A. (1997), "Improved G factor method for columns in unbraced frames", Scientific Bulletin, Faculty of Engrg., Ain Shams University, Cairo, Egypt, Accepted for publication.
  9. Fraser, D. (1983), "Evaluation of effective length factor in braced frames", Canadian J. Civ. Engrg., 10, 18-26. https://doi.org/10.1139/l83-003
  10. Goncalves, R. (1992), "New stability equation for columns in braced frames", J. Struct. Engrg., ASCE, 118(7), 1853-1870. https://doi.org/10.1061/(ASCE)0733-9445(1992)118:7(1853)
  11. Hajjar, J.F. and White, D.W. (1994), "The accuracy of column stability calculations in unbraced frames and the influence of columns with effective length factor less than one", AISC Eng. J., 31(3), 81-97.
  12. LeMessurier, W.J. (1977), "A practical method of second order analysis", Part 2-Rigid frames, Eng. J., 14(2), 49-67.
  13. Lui, E.M. (1992), "A novel approach for K factor determination", AISC Eng. J., 29(4), 150-159.
  14. Yura, J.A. (1971), "The effective length of columns in unbraced frames", AISC Eng. J., 8(2), 37-42.

피인용 문헌

  1. Semi-analytical buckling analysis of reinforced concrete columns exposed to fire vol.71, 2015, https://doi.org/10.1016/j.firesaf.2014.11.018
  2. Exact buckling load of a restrained RC column vol.27, pp.3, 2007, https://doi.org/10.12989/sem.2007.27.3.293
  3. Effective buckling length of steel column members based on elastic/inelastic system buckling analyses vol.26, pp.6, 2007, https://doi.org/10.12989/sem.2007.26.6.651
  4. Buckling analysis of semi-rigid gabled frames vol.55, pp.3, 2015, https://doi.org/10.12989/sem.2015.55.3.605