New Design Rules for the Shear Strength of LiteSteel Beams with Web Openings
Publication: Journal of Structural Engineering
Volume 139, Issue 5
Abstract
A LiteSteel beam (LSB) is a new cold-formed steel hollow flange channel section produced using a patented manufacturing process involving simultaneous cold-forming and dual electric resistance welding. The LSBs are commonly used as floor joists and bearers with web openings in residential, industrial, and commercial buildings. Their shear strengths are considerably reduced when web openings are included for the purpose of locating building services. However, no research has been undertaken on the shear behavior and strength of LSBs with web openings. Therefore, experimental and numerical studies were undertaken to investigate the shear behavior and strength of LSBs with web openings. In this research, finite-element models of LSBs with web openings in shear were developed to simulate the shear behavior and strength of LSBs including their buckling characteristics. They were then validated by comparing their results with available experimental test results and used in a detailed parametric study. The results showed that the current design rules in cold-formed steel structures design codes are very conservative for the shear design of LSBs with web openings. Improved design equations have been proposed for the shear capacity of LSBs with web openings based on both experimental and parametric study results. An alternative shear design method based on an equivalent reduced web thickness was also proposed. It was found that the same shear strength design rules developed for LSBs without web openings can be used for LSBs with web openings provided the equivalent reduced web thickness equation developed in this paper is used. This is a significant advancement as it simplifies the shear design methods of LSBs with web openings considerably.
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Acknowledgments
The authors thank the Australian Research Council and OneSteel Australian Tube Mills for financial support and the Queensland University of Technology for providing the necessary facilities and support to conduct this research project. The authors also thank Mr. Ross Dempsey, Manager (Research and Testing, OneSteel Australian Tube Mills), for technical contributions and overall support to the many different phases of this research project.
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Information
Published In
Journal of Structural Engineering
Volume 139 • Issue 5 • May 2013
Pages: 640 - 656
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Jun 16, 2011
Accepted: Dec 29, 2011
Published online: Jan 2, 2012
Published in print: May 1, 2013
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