DOI QR코드

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Minimum stiffness of bracing for multi-column framed structures

  • Aristizabal-Ochoa, J. Dario (National University, School of Mines)
  • 발행 : 1998.04.25

초록

A method that determines the minimum stiffness of baracing to achieve non-sway buckling conditions at a given story level of a multi-column elastic frame is proposed. Condensed equations that evaluate the required minimum stiffness of the lateral and torsional bracing are derived using the classical stability functions. The proposed method is applicable to elastic framed structures with rigid, semirigid, and simple connections. It is shown that the minimum stiffness of the bracing required by a multi-column system depends on: 1) the plan layout of the columns; 2) the variation in height and cross sectional properties among the columns; 3) the applied axial load pattern on the columns; 4) the lack of symmetry in the loading pattern, column layout, column sizes and heights that cause torsion-sway and its effects on the flexural bucking capacity; and 5) the flexural and torsional end restrains of the columns. The proposed method is limited to elastic framed structures with columns of doubly symmetrical cross section with their principal axes parallel to the global axes. However, it can be applied to inelastic structures when the nonlinear behavior is concentrated at the end connections. The effects of axial deformations in beams and columns are neglected. Three examples are presented in detail to show the effectiveness of the proposed method.

키워드

참고문헌

  1. ACI Committee 318 (1992), "Building code requirements for reinforced concrete and commentry (ACI 318-89/318R-89, Revised 1992)", American Concrete Institute, Detroit, 347.
  2. Aristizabal-Ochoa, J. Dario (1994a), "K-factor for columns in any type of construction: nonparadoxical approach", J. Struct. Engrg., ASCE, 120(4), 1272-1290. https://doi.org/10.1061/(ASCE)0733-9445(1994)120:4(1272)
  3. Aristizabal-Ochoa, J. Dario (1994b), "Slenderness K-factor for leaning columns", J. Struct. Engrg., ASCE, 120(10), 2977-2991. https://doi.org/10.1061/(ASCE)0733-9445(1994)120:10(2977)
  4. Aristizable-Ochoa, J. Dario (1994c), "Stability of columns under uniform load with semirigid connections", J. Struct. Engrg., ASCE, 120(11), 3212-3222. https://doi.org/10.1061/(ASCE)0733-9445(1994)120:11(3212)
  5. Aristizable-Ochoa, J. Dario (1995), "Story stability and minimum bracing in RC framed structures: a general approach", ACI Structural Journal, 92(6), Nov-Dec., 735-744.
  6. Aristizable-Ochoa, J. Dario (1996), "Braced, partially braced, and unbraced columns: complete set classical stability equations", Structural Engineering and Mechanics, Int., Journal, 4(4), 365-381. https://doi.org/10.12989/sem.1996.4.4.365
  7. Cunningham, R. (1990), "Some aspects of semi-rigid connections in structural steel-work", Structural Engineering, 68(5), 85-92.
  8. Gerstle, K.H. (1988), "Effects of connections of frames", Steel Beam-to Column Building Connections, W. F. Chen, ed., Elsevier Science Publishers Ltd., New York, N.Y., pp. 241-267.
  9. Manual of Steel Construction-(1990), Allowable Stress Design, Ninth Edition, AICS, 1990, (part 3).
  10. Manual of Steel Construction-(1986), Load & Resistance Factor Design, First Edition, AISC, (part 2).
  11. Manual of Steel Construction-(1994), Load & Resistance Factor Design, 2nd Edition, AISC.
  12. Salmon, C.G. and Johnson, J.E. (1980), Steel Structures: Design and Behavior, 2nd Edition, Harper and Row, Chapter 14.
  13. Timoshenko, S.P. and Gere, J.M. (1961), Theory of Elastic Stability, 2nd. Ed., McGraw-Hill, New York, N.Y.
  14. Wang, C.K. (1983), Intermediate Structural Analysis, McGraw-Hill Inc., New York, Chapter 20.
  15. Xu, L. and Grierson, D.E. (1993), "Computer-automated design of semirigid steel frameworks", Journal of Structural Engineering, ASCE, 119(6), 1740-1760. https://doi.org/10.1061/(ASCE)0733-9445(1993)119:6(1740)

피인용 문헌

  1. Column Stability and Minimum Lateral Bracing: Effects of Shear Deformations vol.130, pp.10, 2004, https://doi.org/10.1061/(ASCE)0733-9399(2004)130:10(1223)
  2. Discussion of “Buckling and Second-Order Effects in Dual Shear-Flexural Systems” by Tong Gengshu, Yong-Lin Pi, Mark Andrew Bradford, and Francis Tin-Loi vol.137, pp.2, 2011, https://doi.org/10.1061/(ASCE)ST.1943-541X.0000046
  3. Buckling of Flexural-Shear Bracing System and Its Braced Steel Frames vol.18, pp.11, 2015, https://doi.org/10.1260/1369-4332.18.11.1831
  4. Classic Buckling of Three-Dimensional Multicolumn Systems under Gravity Loads vol.128, pp.6, 2002, https://doi.org/10.1061/(ASCE)0733-9399(2002)128:6(613)
  5. Stability of columns with semi-rigid connections including shear effects using Engesser, Haringx and Euler approaches vol.33, pp.3, 2011, https://doi.org/10.1016/j.engstruct.2010.12.008