Fire resistance assessment of automated rack supported warehouses

Automated Rack Supported Warehouses (ARSW) combine the structural efficiency of metal construction with automated machines for handling the stored products. A fundamental distinction exists between traditional Steel Racks (SR) and ARSW, indeed ARSW are self-bearing rack structures committed to support, besides self-weight and weight of products, also environmental loads (i.e., wind, snow and seismic action) and all the other non-structural elements such as clads, equipment, etc. The peculiarity of these structures makes them a topic of great interest both for the scientific community and for the manufacturers of industrial racks. In the last years, a lot of research has been carried out to better understand the behaviour of these structures from the seismic point of view, while their behaviour in case of fire is still poorly known. Since the lack of regulations and technical references, this paper aims to provide a state of the art on ARSW structures in case of fire, with a discussion of the most critical aspects. For this reason, this paper provides first results about an advanced thermos-mechanical analysis of a case study, by considering a fire model that allows us to consider the vertical and horizontal propagation starting from a localized fire and providing a comparison between the capacity models that the regulations in case of fire propose for cold-formed steel members (CFS), which mainly made these structures.