Seismic Performance of Currently Designed Automated Rack Supported Warehouses

– The paper analyses the seismic performance of Automated Rack Supported Warehouses (ARSWs), huge steel buildings developed for an optimized storage and management of palletized goods. These buildings have a load-bearing structure made up of steel racks that have the same peculiar characteristic of traditional steel racks, but with the relevant difference that the formers are demanded to resist to all the types of loads (e.g., wind, snow, earthquakes, gravity loads) while the latter to only the storage loads and the eventual associated inertial forces in case of earthquakes. Despite this relevant difference, the ARSWs have inherited almost all the structural characteristics of the traditional steel racks, resulting often in a non-satisfactory structural behaviour, as highlighted by recent collapses of ARSWs after seismic events. With the aim of assessing the seismic behaviour of ARSWs designed following the current guidelines, the paper presents 5 ARSW structures designed from 5 big European companies, analysing the different design approaches and hypothesis, and the consequences of these different choices in terms of seismic demand and performance. The results presented point out that a proper and dedicated design approach is needed for ARSWs.