Performance of External Light Steel Walls Lined with Steel Cladding Under Wildfire Exposure Conditions

Bushfires/wildfires are a frequent and destructive natural hazard that occurs in many regions worldwide. With the adverse effects of climate change and the increasing number of people living in the Bushland Urban Interface (BUI), there is a need to incorporate bushfire impacts in the design and construction of buildings. However, there are limited studies on external building elements (walls, roof etc.) and the use of different fire curves in assessing them. Therefore, this numerical modelling-based study investigated the performance of light steel framed walls lined with thin steel cladding on the external side under two different bushfire exposure conditions based on previous research studies and testing standards. The results were then compared with the performance of external wall systems without steel cladding to quantify the improvements/deterioration under each fire curve. The model predictions showed significant improvements in the performance of external wall systems when steel cladding was used. This study further emphasises the importance of using the appropriate fire curves and compares the change in predicted integrity based on each fire curve. The outcomes of this study are important to improve the resilience of buildings in bushfire-prone areas and thereby reduce the costs of retrofitting.