A safety index for hospital buildings

Seismic vulnerability assessment is of paramount importance for existing critical structures, e.g. health care centers and hospital buildings. Numerous surveys carried out in the aftermath of recent earthquakes have shown that the performance of hospitals is not impaired by the structural damage; conversely, functional breakdowns are major threats. Nonstructural components in buildings are rarely designed with the same level of details used for structural elements. In the present paper a checking/recording document is proposed, including the vulnerability of nonstructural elements and medical equipment; the overall seismic vulnerability is then estimated by a vulnerability index referred to both the functional and structural parts of the buildings. The simplified methodology, developed on the basis of studies carried out by Pan American Health Organization (PAHO) and World Health Organization (WHO), finally provides a safety index as function of all the parameters that characterize the seismic risk: vulnerability, hazard and exposition. The simplified procedure is applied to two cases of study, then the detailed structural analysis is developed by means of pushover analyses based on lumped plasticity models. The obtained results allow to check the effectiveness of the proposed methodology directing the future research development