How Mitigating is Base Isolation

The paper proposes a versatile approach to asses the degree and the efficiency of seismic mitigation via passive protection of steel multistory 3D skeletal structures. Present contribution introduces the results and the proposed approach of assessing the effectiveness of seismic mitigation associated passive protection via elastomeric base isolators. The structure has been designed according to EUROCODE 3 provisions for steel structures located in seismic areas.

The applied static loading is of spatial pushover (modal distribution) form applied simultaneously on both orthogonal directions. The time history type loading consists of the recorded Vrancea 1977 (Romania) accelerogram – a reference earthquake in this country – and two artificially generated accelerograms. A post elastic behavior has been allowed for. The obtained results are associated to the usual seismic performance based analysis parameters.