Steel storage pallet racks are framed steel structures commonly used in the logistic field. According to the European practice, they are built with cold-formed steel profiles. Vertical and horizontal elements are connected with mechanical joints and special elements are used for the base connections. The design of these structures is usually performed by adopting the 'design by testing' approach. This procedure asks for the experimental characterization of the main racks components and sub-assemblies, which allows identifying the parameters needed for the safety checks and the development of reliable FE models. Recent seismic events clearly showed the need for improvements in the knowledge of the seismic response not only of the components but also of the whole structure. As a contribution to this topic, an experimental study of the seismic response of full-scale rack frames is currently in progress. At this aim, a testing set-up for full-scale structures, with a maximum height of 22m, was designed and realized. In this paper, the main features of the experimental set-up and the results of two push-over tests on a commercial two-bay four-level pallet rack are described and discussed. Finally, the results of FE analyses are presented.

<p>Adjustable storage pallet racks are framed structures commonly made of cold-formed steel profiles. The performance of these structures is strongly influenced by the beam-to-column and the base- plate joints behaviour. The key role of joints is even more significant in seismic loading conditions. The complexity of their non-linear and non-symmetric behaviour calls for their experimental characterisation both in monotonic and cyclic range. In recent years, attention has been paid to the study of beam-to-column joints, while the knowledge on the base-plate joints response is still quite limited. This gap is even more evident when the cross-aisle (transversal) direction and the cyclic range are considered. The research presented in this paper focuses on the monotonic and cyclic experimental response of a typical rack base-plate joint, tested both in down-aisle (longitudinal) and cross-aisle direction. The main features and outcomes of the study are presented and discussed.</p>

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The strategies worldwide adopted nowadays for static and seismic rack design are based on approaches efficiently developed for the traditional carpentry frames, i.e. realized with hot-rolled bi-symmetric cross-section profiles. An open question is hence related to the effective degree of safety of these design rules when applied to racks, i.e. to structures realized by means of thin-walled cold-formed members, highly sensitive to second order effects. A study is currently in progress to define reliable seismic design procedures accounting for rack key features. In the framework of different planned activities, an ad hoc experimental equipment for testing full-scale racks under variable load conditions was developed. This paper presents the key features of the testing set-up, equipped with independent dynamic actuators, which allow applying vertical and horizontal loads.