Shaking table tests on a passive equipment isolation system for earthquake protection

The present work refers to steel frame structures in industrial plants. A passive isolation system for seismic protection of a considerable equipment, already present on a frame support structure and rigidly constrained to it, is investigated through both numerical simulations (1+1 DOF system) and shaking table tests on a 1:5 scale two-story steel frame structure. The equipment (e.g. a pipeline, a compressor unit,...) is modelled as a rigid mass. The optimal design is determined by minimizing the dynamic response of the isolated mass. In order to ensure strenght and serviceability, the response of the frame is also monitored.