Seismic vulnerability reduction for historical buildings: the case study of House of mosaics

The present paper explores the possibility to obtain the reduction of seismic vulnerability of historical buildings through subsoil treatments, in order to reduce the seismic actions. The study is motivated by the unsatisfactory degree of protection of many historical buildings with respect of seismic risk, and by the in-adequacy and/or the inability to adopt the reinforcement or base isolation methodologies used on the new con-structions. The issue has been addressed through a multi-disciplinary approach. A suitable case study was se-lected, i.e. the ancient Villa Favorita park on the sea in Herculaneum, a site well-characterized in terms of geology, stratigraphy, and mechanical properties of the soil. These features allowed to simulate the seismic subsoil response by 1D modeling, with site effects exclusively induced by the stratigraphy. The seismic beha-viour of the building, with high historical-architectural value, was accurately reproduced by a 3D model. The study was conducted through uncoupled numerical analysis of the site response and the structure in elevation, analyzing the effects of possible artificial variations of soil properties on the seismic safety of the building.