Experimental assessment of the seismic behavior of unbraced steel storage pallet racks

This paper presents the experimental results of full scale push-over tests performed in the down-aisle (longitudinal) direction on fully-loaded unbraced specimens. In particular, experimental global capacity curves of the tested specimens are presented, discussing the key factors influencing the racks' response, as well as the failure mechanisms of the different rack typologies. Furthermore, the behavior factor (q) values of each specimen are derived from re-analysis of the test results. Vulnerability of unbraced racks to soft-storey mechanism is demonstrated, highlighting its causes. Design guidelines are provided in order to guarantee a globally homogenous ductility under seismic actions, along with the new safety requirements for the design of the floor connections of unbraced racks.