The role of frame members and sheathing in partition wall panels subjected to compression

This paper presents an experimental study on the role of frame members and sheathing by means of strain/stress distributions in each of the constituents of a cold-formed steel wall panel. Vertical compression loading was applied, and strain gauges were extensively used during the tests. At a given cross-section of the middle stud, strains/stresses experienced by its flanges are found to be significantly different from those on the web, indicating that the middle stud is not balanced in simple compression mode. However, the averaged stress on the flanges and that on the web follow the same trend as that recorded by the load cell, and can be used to work out the load carried by the stud. Screw connections between the stud and the board not only restrain the lateral displacement of the stud, but also support and re-distribute a portion of the load to the board and then to the bottom track. Upon loading, the axial force experienced by a typical screw is negligibly small initially, increasing slowly with load until substantial stud buckling occurs, resulting in often its pulling-out from the board or the stud/track. The board acts as a shearing member to steady the whole panel, a supporting member to enhance the overall/local buckling performance of the middle stud and sidetracks, as well as a structural member to support part of the vertical load.