Base isolation for seismic retrofitting of damaged buildings

The paper deals with the retrofitting of r/c buildings damaged by the earthquake adopting the base-isolation. The case of one building is analyzed in detail. The seismic vulnerability of the building in the original configuration is assessed. A classification of the possible conventional works concerning repair, retrofit, seismic enhancement is carried out dealing with the structural effectiveness, impact, control in application and lifetime, related indirect works, cost. The main result is a tentative classification of the issues related to the insertion of a base-isolation system below an existing building aimed at its seismic enhancement, avoiding or relied strongly limiting other works in the building elevation. The retrofitting strategies, the enhancement levels, the application solutions are critically revised statement under the experience of the real cases faced with, also paying attention to the cost-effectiveness ratios.