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Determination of slip modulus of cold-formed steel composite members sheathed with plywood structural panels

  • Karki, Dheeraj (School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney (UTS)) ;
  • Far, Harry (School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney (UTS)) ;
  • Al-hunity, Suleiman (School of Civil and Environmental Engineering, Faculty of Engineering and Information Technology, University of Technology Sydney (UTS))
  • Received : 2021.10.20
  • Accepted : 2022.02.26
  • Published : 2022.05.25

Abstract

An experimental investigation to study the behaviour of connections between cold-formed steel (CFS) joist and plywood structural panel is presented in this paper. Material testing on CFS and plywood was carried out to assess their mechanical properties and behaviour. Push-out tests were conducted to determine the slip modulus and failure modes of three different shear connection types. The employed shear connectors in the study were; size 14 (6mm diameter) self-drilling screw, M12 coach screw, and M12 nut and bolt. The effective bending stiffness of composite cold-formed steel and plywood T-beam assembly is calculated based on the slip modulus values computed from push-out tests. The effective bending stiffness was increased by 25.5%, 18% and 30.2% for self-drilling screw, coach screw, nut and bolt, respectively, over the stiffness of cold-formed steel joist alone. This finding suggests the potential to enhance the structural performance of composite cold-formed steel and timber flooring system by mobilisation of composite action present between timber sheathing and CFS joist.

Keywords

Acknowledgement

The authors would like to thank Peter Brown of the UTS tech lab for providing guidance throughout the testing.

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