QUSDRA APPROACH: QUICK SEISMIC DESIGN OF STEEL STORAGE RACKS

The paper is focused on the seismic performance of steel storage pallet racks, which represent a very competitive solution, widely used to store goods and materials. In particular, the design strategy herein proposed is based on a procedure which directly correlate the static and the seismic rack performance using the so-called Incremental Dynamic Analysis (IDA) approach. Despite this approach is a well-established analysis method, generally used for defining the risk associated with seismic events, it is rarely employed in the routine design of steel racks. In fact, independently of the complexity of the racks under investigation, only the modal response spectrum analysis (MRSA) is usually adopted, neglecting hence some non-negligible peculiarities of these structures. This is mainly due to the lack of time during the design phases. The proposed procedure, named QUSDRA (QUick Seismic Design of steel storage RAcks), allows designers to choose the more convenient structural solution by considering both costs and the key structural performance parameters (i.e. reduction of the load carrying capacity, transient interstorey drift and residual interstorey drift), with limited computational efforts. In fact, QUSDRA method is directly based on an IDA database which, once created, can be used for the rack design on different seismic area. In order to better understand the key phases of the procedure, a step-by-step case study is presented, highlighting the main advantages associated with the proposed approach.