Seismic Vulnerability Reduction for Historical Buildings with Non-Invasive Subsoil Treatments: The Case Study of the Mosaics Palace at Herculaneum

The possibility to reduce the seismic vulnerability of historical buildings through subsoil treatments aimed to modify the seismic site response is a recent advancement in earthquake engineering: the paper presents the case study of the Mosaics Palace, located close to the archeological site of Herculaneum which is about 10 km south of Naples. The study was developed through uncoupled dynamic analysis of the seismic site response and of the masonry structure. All the available information on the subsoil were collected and integrated with on-purpose in situ tests; a 1-D subsoil model was adopted for linear equivalent seismic response analysis. Several hypotheses of soil treatments, spanning from soft to stiff grouted layers, were taken into account. On the other hand, the capacity of the structure was defined by a pushover analysis and compared to the seismic demand for each soil treatment option, allowing for a final assessment of the effectiveness of the proposed technology on the building performance.