Stiffness and strength characteristics of cold-formed steel clip angles subjected to pull-through failures

Load bearing cold-formed steel clip angles are commonly used in various connections, subjected to different loading conditions. This numerical parametric study was performed in order to investigate the effect of various parameters on pull-through strength of fasteners on the anchored leg of cold-formed steel clip angles. In this regard, a finite element analysis is conducted, using ABAQUS program, to model the specimens subjected to tension forces. The finite element modeling is verified, using the existing tested clip angles and the ability of the validated finite element models in predicting the pull-through strength of other clip angle cases is evaluated, by comparing the obtained results with the experimental results. This parametric study provides a detailed information on the effect of any effective parameters, such as clip angle geometry, basic mechanical properties, and screw fastener head or washer sizes on the pull-through failures of bearing clip angles. According to the results, although the effects of parameters, such as screw fastener head or washer sizes and mechanical properties, on the pull-through strength are significant, the effect of clip angle geometry can be neglected. Finally, a suitable design equation is proposed to calculate the pull-through failure of load bearing clip angles. Moreover, a new equation is presented to calculate elastic stiffness of cold-formed steel clip angles, using a simple analytical model. The results obtained from this equation are in a proper agreement with the initial slope of force-displacement curves.