TY - JOUR
T1 - Sheathing Bracing Requirements for Cold-formed Steel Wall Panels
T2 - Experimental Investigation
AU - Selvaraj, Sivaganesh
AU - Madhavan, Mahendrakumar
N1 - Funding Information:
The investigation reported in this paper was funded by Science and Engineering Research Board (SERB) Research Grant ( SB/S3/CEE/046/2014 ) from the Department of Science and Technology (DST), Government of India. The first author would like to acknowledge the financial assistance received from this project. The authors would like to gratefully acknowledge Pennar Engineered Building Systems Ltd., Hyderabad for their help in fabricating the test specimens required for experimental investigation.
Publisher Copyright:
© 2019 Institution of Structural Engineers
PY - 2019/6
Y1 - 2019/6
N2 - This paper presents an experimental investigation to arrive at minimum sheathing requirements to inhibit the lateral torsional buckling (LTB) of the hat-shaped cold-formed steel (CFS) member subjected to out-of-plane loading. This study also describes the need for explicit minimum sheathing requirement provisions for different geometries of CFS structural members which are currently absent in the present design specifications. The design parameters for wall panels such as slenderness of the CFS member, the thickness of the sheathing board, the spacing between the fasteners that connect the sheathing and CFS member are considered in the experimental tests. A total of 30 full-scale tests (24 sheathed panels and 6 unsheathed tests) were carried out to study the behaviour of unsheathed CFS stud, sheathed panel and to determine their corresponding ultimate moment capacities. While all the unsheathed inverted hat-shaped CFS studs failed in LTB, the CFS stud with the gypsum sheathing effect did not undergo lateral torsional buckling and the sheathing effect led to reach its corresponding yield moment which is significantly higher than the lateral torsional buckling moment of the unsheathed CFS stud. It was also observed that until the failure of CFS stud, the gypsum sheathing did not experience damage (no bearing or pull-through failure). Based on the experimental investigation, it is shown that the gypsum sheathing board of thickness (tb) 12.5 mm with intermediate fastener spacing (df) 300 mm is sufficient to inhibit the LTB of the inverted hat shaped CFS studs. In addition, the analytical investigations were also performed to check the strength of the sheathing bracing. The analytical investigation results showed a good agreement with the experimental results in terms of sheathing failure mode and bracing requirement. Hence, the explicit minimum sheathing requirements to inhibit the LTB of the different geometry of CFS studs are suggested conservatively by considering the practicality of the wall construction.
AB - This paper presents an experimental investigation to arrive at minimum sheathing requirements to inhibit the lateral torsional buckling (LTB) of the hat-shaped cold-formed steel (CFS) member subjected to out-of-plane loading. This study also describes the need for explicit minimum sheathing requirement provisions for different geometries of CFS structural members which are currently absent in the present design specifications. The design parameters for wall panels such as slenderness of the CFS member, the thickness of the sheathing board, the spacing between the fasteners that connect the sheathing and CFS member are considered in the experimental tests. A total of 30 full-scale tests (24 sheathed panels and 6 unsheathed tests) were carried out to study the behaviour of unsheathed CFS stud, sheathed panel and to determine their corresponding ultimate moment capacities. While all the unsheathed inverted hat-shaped CFS studs failed in LTB, the CFS stud with the gypsum sheathing effect did not undergo lateral torsional buckling and the sheathing effect led to reach its corresponding yield moment which is significantly higher than the lateral torsional buckling moment of the unsheathed CFS stud. It was also observed that until the failure of CFS stud, the gypsum sheathing did not experience damage (no bearing or pull-through failure). Based on the experimental investigation, it is shown that the gypsum sheathing board of thickness (tb) 12.5 mm with intermediate fastener spacing (df) 300 mm is sufficient to inhibit the LTB of the inverted hat shaped CFS studs. In addition, the analytical investigations were also performed to check the strength of the sheathing bracing. The analytical investigation results showed a good agreement with the experimental results in terms of sheathing failure mode and bracing requirement. Hence, the explicit minimum sheathing requirements to inhibit the LTB of the different geometry of CFS studs are suggested conservatively by considering the practicality of the wall construction.
KW - Cold-formed steel
KW - Lateral torsional buckling
KW - Sheathing bracing
KW - Sheathing requirement
KW - Wall panel
UR - http://www.scopus.com/inward/record.url?scp=85060723430&partnerID=8YFLogxK
U2 - 10.1016/j.istruc.2019.01.005
DO - 10.1016/j.istruc.2019.01.005
M3 - Journal article
AN - SCOPUS:85060723430
SN - 2352-0124
VL - 19
SP - 258
EP - 276
JO - Structures
JF - Structures
ER -