An experimental study of screw pull-out in load bearing cold-formed-steel clip angles

Abstract

Load bearing cold-formed steel clip angles are one of the commonly used connectors in lightweight cold-formed steel structures. These connectors may fail at their screw connections due to pull-out failure when the screw pulls out of the plate under tension loading conditions. These localized connection failures can cause undesirable failures by dislocating both clip angle and sub-plates. Therefore, a detailed experimental study was carried out to investigate the pull-out failures of load bearing cold-formed steel clip angles considering different parameters such as clip angle configuration, clip angle thickness, screw diameter size, screw thread pitch, number of screws and screw location. This paper presents the test results conducted in this study and compares them with existing pull-out design standard equations. Also, a design equation with a resistance reduction factor is developed and suggested in order to accurately determine the pull-out strength of the cold-formed steel clip angles.