Pull-out failure capacities of cold-formed steel batten screw connections at sub-zero temperatures

Abstract

Cold-formed steel (CFS) roof and wall cladding systems are used worldwide, and are constructed using high-strength, thin steel battens and claddings. In North American countries, which are frequently subjected to blizzards (winter storms), these cladding systems are particularly vulnerable to pull-out failures during combined windstorm and snowy conditions. Despite extensive research studies investigating the pull-out failure mechanism and the critical parameters of screw connections between cladding and battens at ambient temperature, the behaviour of these connections under blizzard conditions has not been experimentally investigated. To fill this knowledge gap, an experimental study was undertaken that included 144 laboratory tests of screw connections in battens of varying grades and thicknesses, and three distinct types of screws. The pull-out failure capacities of screw connections in battens were evaluated under wind suction loading at four different temperatures, including ambient and sub-zero temperatures. The results of the study provided insights into the pull-out failure mechanisms of screw connections in battens and enabled the development of suitable design rules for combined wind action and sub-zero temperature conditions. The findings of this study are expected to be of significant value to engineers and building designers who are involved in the construction of lightweight cold-formed steel buildings.