Collapse Fragility Curves for Non-residential Older Single-Storey Steel Buildings

The paper describes the seismic response of non-residential single-story steel buildings designed in the decade 1980s–1990s in Italy. To this end, multiple building archetypes were designed following code regulations enforced at that time. The selected case studies are characterized by (i) a main truss system in the transverse building direction and (ii) a concentric braced system in the longitudinal building direction. Various structural schemes and two alternative brace cross section types were considered. 3D non-linear finite element models were built and analysed using OpenSees. The analysis was carried out considering the contribution of envelope panels to the seismic response by using two different types of cladding panels. Empirical fragility curves allow to highlight the role of the structural scheme, the type of envelope panels and the increasing level of the building site seismic hazard.