Abstract:
Abstract: Steel roofs made of thin cold-formed steel roof claddings and battens are widely used in low-rise
residential and industrial buildings all around the world. However, they suffer from premature localised pullthrough
failures in the batten to rafter connections during high wind events. A recent study proposed a suitable
design equation for the pull-through failures of thin steel roof battens. However, it was limited to static wind uplift
loading. In contrast, most cyclone/storm events produce cyclic wind uplift forces on roofs for a significantly long
period, thus causing premature fatigue pull-through failures at lower loads. Therefore, a series of constant amplitude
cyclic load tests was conducted on small and full scale roof panels made of a commonly used industrial roof batten
to develop their S-N curves. A series of multi-level cyclic tests, including the recently introduced low-high-low
(LHL) fatigue loading test, was also undertaken to simulate a design cyclone. Using the S-N curves, the static pullthrough
design capacity equation was modified to include the effects of fatigue. Applicability of Miner’s rule was
evaluated in order to predict the fatigue damage caused by multi-level cyclic tests such as the LHL test, and suitable
modifications were made. The combined use of the modified Miner’s law and the S-N curve of roof battens will
allow a conservative estimation of the fatigue design capacity of roof battens without conducting the LHL tests
simulating a design cyclone. This paper presents the details of this study, and the results.
