Improving the Shear Capacities of Lipped Channel Beams with Web Openings Using Plate Stiffeners
Publication: Journal of Structural Engineering
Volume 141, Issue 11
Abstract
Cold-formed steel lipped channel beams (LCBs) are used extensively in residential, industrial, and commercial buildings as load-bearing structural elements. Their shear capacities are considerably reduced when the web openings are included for the purpose of locating building services. Past research has shown that the shear capacities of LCBs were reduced by up to 70% due to the inclusion of these web openings. Hence there is a need to improve the shear capacities of LCBs with web openings. A cost-effective way of eliminating the detrimental effects of large web openings is to attach suitable stiffeners around the web openings and restore the original shear strength and stiffness of LCBs. Hence detailed experimental studies were undertaken to investigate the behavior and strength of LCBs with stiffened web openings subject to shear, and combined bending and shear actions. Both plate and stud stiffeners, with varying sizes and thicknesses, were attached to the web elements of LCBs using different screw-fastening arrangements. Simply supported test specimens of LCBs with aspect ratios of 1.0 and 1.5 were loaded at midspan until failure. Numerical studies were also undertaken to investigate the strength of LCBs with stiffened web openings. Finite-element models of LCBs with stiffened web openings under shear, and combined bending and shear actions, were developed to simulate the behavior of the tested LCBs. The developed models were then validated by comparing their results with experimental results and were used in further studies. Both experimental and finite-element analysis results showed that the stiffening arrangements recommended by past research and available design guidelines are not adequate to restore the original shear strengths of LCBs. Therefore, new stiffener arrangements were proposed based on screw fastened plate stiffeners. The details of the research reported in this paper are presented.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The writers would like to thank the Queensland University of Technology for providing the necessary facilities and support to conduct the research reported in this paper. The writers would also like to thank Mr. Liam Rea and Mr. Andre Dos Santos for their valuable assistance in performing the shear tests of stiffened LCBs.
References
ABAQUS 6.7 [Computer software]. Pawtucket, RI, Hibbit Karisson and Sorensen.
AISI (American Iron and Steel Institute). (2004). Supplement to the standard for cold-formed steel framing—Prescriptive method for one and two family dwellings, Washington, DC.
AISI (American Iron and Steel Institute). (2007). North American specification for the design of cold-formed steel structural members, Washington, DC.
AISI (American Iron and Steel Institute). (2012). North American specification for the design of cold-formed steel structural members, Washington, DC.
Anapayan, T., and Mahendran, M. (2012a). “Improved design rules for hollow flange sections subject to lateral distortional buckling.” Thin Walled Struct., 50(1), 128–140.
Anapayan, T., and Mahendran, M. (2012b). “Numerical modelling and design of LiteSteel beams subject to lateral buckling.” J. Constr. Steel Res., 70(3), 51–64.
Anapayan, T., Mahendran, M., and Mahaarachchi, D. (2011). “Section moment capacity tests of LiteSteel beams.” Thin Walled Struct., 49(4), 502–512.
BlueScope Lysaght. (2010). Cold-formed section CFS-1 section properties, Sydney, Australia.
HKS (Hibbitt, Karlsson and Sorensen). (2007). ABAQUS user’s manual, New York.
Keerthan, P., and Mahendran, M. (2010). “Experimental studies on the shear behaviour and strength of litesteel beams.” Eng. Struct., 32(10), 3235–3247.
Keerthan, P., and Mahendran, M. (2011). “New design rules for the shear strength of LiteSteel beams.” J. Constr. Steel Res., 67(6), 1050–1063.
Keerthan, P., and Mahendran, M. (2013a). “Improved shear design rules for lipped channel beams with web openings.” J. Constr. Steel Res., 97(6), 127–142.
Keerthan, P., and Mahendran, M. (2013b). “Shear buckling characteristics of cold-formed steel channel beams.” Int. J. Steel Struct., 13(3), 385–399.
Keerthan, P., and Mahendran, M. (2013c). “Suitable stiffening systems for LiteSteel beams with web openings subjected to shear.” J. Constr. Steel Res., 80(3), 412–428.
OATM (OneSteel Australian Tube Mills). (2008). Design of LiteSteel beams, Brisbane, Australia.
Pennock, R. W. (2001). “Strength of light gauge cold-formed steel joists with web perforation.” Senior Rep., Univ. of New Brunswick, NB, Canada.
SA (Standards Australia). (2005). “Australia/New Zealand standard AS/NZS 4600 cold-formed steel structures.” AS/NZS 4600, Sydney, Australia.
Seo, J. K., and Mahendran, M. (2011). “Plastic bending behavior and section moment capacities of mono-symmetric LiteSteel beams with web openings.” Thin Walled Struct., 49(4), 513–522.
Sivakumaran, K. S. (2008). “Reinforcement schemes for CFS joists having web openings.”, Dept. of Civil Engineering, McMaster Univ., Hamilton, ON, Canada.
Information & Authors
Information
Published In
Copyright
© 2015 American Society of Civil Engineers.
History
Received: Mar 19, 2014
Accepted: Sep 29, 2014
Published online: Feb 17, 2015
Discussion open until: Jul 17, 2015
Published in print: Nov 1, 2015
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.