Fatigue design of thin-walled steel roof battens

Thin-walled steel roofing systems of low-rise buildings are exposed to highly fluctuating suction pressures during cyclones and thus they are often subject to premature, low cycle fatigue pull-through failures at steel roof batten (top hat) to rafter connections. Current fatigue design practice is to undertake full-scale airbox tests of the entire roofing system using the Low-High-Low (LHL) cyclic test method, which is timeconsuming and expensive. Therefore, a detailed experimental research study consisting of static and constant amplitude cyclic tests was undertaken and a simple, unified static-fatigue pull-through design capacity equation was developed for steel roof battens. Alternative design methods such as designs based on fatigue limit and 10,000 wind load cycles were discussed along with simplified cost analyses