Biaxial Bending of Cold-Formed Z-Beams
Publication: Journal of Structural Engineering
Volume 125, Issue 11
Abstract
This paper reports the results of ten biaxial bending tests on unbraced, simply supported, cold-formed steel Z-beams loaded at midspan in planes inclined to the major principal plane. These results and those of six beams loaded in the major principal plane are compared with analytical predictions and with simple design approximations. The tests show that the beam strengths decrease as the load inclination to the major principal plane increases, and that the strength is higher when the load inclination is toward the web than when it is toward the flange lip. Good agreement is demonstrated between the test results and analytical predictions of the strengths. An extended series of analytical predictions is used to develop simple interaction equations that can be used in the design of eccentrically loaded cold-formed Z-beams.
Get full access to this article
View all available purchase options and get full access to this article.
References
1.
AS/NZS4600 cold-formed steel structures. (1996). Standards Australia/Standards New Zealand, Sydney, Australia.
2.
Celebi, N., Winter, G., and Pekoz, T. (1972). “Diaphragm braced channel and Z-section beams.” Rep. No. 344, Dept. of Structural Engineering, Cornell University, Ithaca, N.Y.
3.
Djugash, A. C. R., and Kalyanaraman, V. (1990). “Experimental study on the lateral buckling of cold-formed beams.” Proc., 10th Int. Spec. Conf. on Cold-Formed Steel Struct., University of Missouri–Rolla, Mo., 363–380.
4.
Djugash, A. C. R., and Kalyanaraman, V. (1994). “Nonlinear analysis of thin-walled members under biaxial bending.” J. Construct. Steel Res., 31, 289–304.
5.
Ellifritt, D. S., Sputo, T., and Haynes, J. R. (1991). “Flexural strength and deflections of discretely braced cold formed steel channel and Zee sections.” Rep. for the American Iron and Steel Institute, University of Florida, Gainesville, Fla.
6.
Ellifritt, D. S., Sputo, T., and Haynes, J. R. (1992). “Flexural capacity of discretely braced C's and Z's.” Proc., 11th Int. Spec. Conf. on Cold-Formed Steel Struct., University of Missouri–Rolla, Mo., 102–129.
7.
Goodier, J. N. ( 1942). “Flexural-torsional buckling of bars of open section under bending, eccentric thrust, or torsional loads.” Bull. No. 28, Cornell University Engineering Experiment Station, Ithaca, N.Y.
8.
Hancock, G. J., and Papangelis, J. P. (1997). THIN-WALL User's Manual. Ctr. for Advanced Structural Engineering, University of Sydney, Sydney, Australia.
9.
Hill, H. N. (1954). “Lateral buckling of channels and z-beams.” Trans., ASCE, 119, 829–841.
10.
Moore, D. (1986). “Non-linear behaviour of thin-walled sections.” Proc., Colloquium on Thin-Walled Metal Struct. in Build., Int. Association for Bridge and Structural Engineering, Stockholm, 35–42.
11.
Pi, Y.-L., Put, B. M., and Trahair, N. S. (1998). “Lateral buckling strengths of cold-formed channel section beams.”J. Struct. Engrg., ASCE, 124(10), 1182–1191.
12.
Pi, Y.-L., Put, B. M., and Trahair, N. S. (1999). “Lateral buckling strengths of cold-formed Z-section beams.” Thin-Walled Struct. (in press).
13.
Pi, Y.-L., and Trahair, N. S. (1994a). “Nonlinear inelastic analysis of steel beam-columns. I: Theory.”J. Struct. Engrg., ASCE, 120(7), 2041–2061.
14.
Pi, Y.-L., and Trahair, N. S. (1994b). “Nonlinear inelastic analysis of steel beam-columns. II: Applications.”J. Struct. Engrg., ASCE, 120(7), 2062–2085.
15.
Put, B. M., Pi, Y.-L., and Trahair, N. S. (1999a). “Lateral buckling tests on cold-formed channel beams.”J. Struct. Engrg., ASCE, 125(5), 532–539.
16.
Put, B. M., Pi, Y.-L., and Trahair, N. S. (1999b). “Bending and torsion of cold-formed channel-beams.”J. Struct. Engrg., ASCE, 125(5), 540–546.
17.
Put, B. M., Pi, Y.-L., and Trahair, N. S. (1999c). “Lateral buckling tests on cold-formed Z-beams.”J. Struct. Engrg., ASCE, 125, 0125 (in press).
18.
Trahair, N. S., and Bradford, M. A. (1998). The behaviour and design of steel structures to AS4100, 3rd Australian Ed., E and FN Spon, London.
19.
Zetlin, L., and Winter, G. (1955). “Unsymmetrical bending of beams with and without lateral bracing.” Proc., ASCE, 81, 774-1, 774-20.
Information & Authors
Information
Published In
History
Received: Feb 9, 1999
Published online: Nov 1, 1999
Published in print: Nov 1999
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.