Numerical Modeling of Thin-Walled Steel Roof Battens Subject to Pull-Through Failures

Extensive damage to light gauge steel roofing systems caused by high wind events such as cyclones and storms has been a concern to the communities living in cyclone/storm prone areas over many years. In recent times, pull-through failures of roof battens occurring in their bottom flange to rafter or truss connection have become the main reason for severe roof failures. Therefore, a detailed experimental study was first undertaken using full-scale and small-scale tests to investigate the pull-through failures of roof battens subject to high wind uplift loads. However, since experimental tests can be expensive and time consuming, the ability to successfully use numerical models is imperative. Hence a detailed numerical study was undertaken by developing suitable finite-element models with the inclusion of a suitable failure criterion to predict the initiation of critical pull-through failures of roof battens that are associated with a tearing fracture around the screw fastener head edge. The overall load versus deformation behavior, ultimate failure loads, and failure modes were compared with the experimental results to validate the developed finite-element models. The ability of the validated finite-element models to accurately predict the pull-through failure loads of roof battens for other cases was evaluated by comparing relevant experimental results. This paper presents the details of this numerical study and the results. (C) 2017 American Society of Civil Engineers.