Trasformazioni ed interventi strutturali svelati dagli eventi sismici: il caso del terremoto Centro Italia 2016

Vernacular architecture in Italian historical centers resulted from the juxtaposition of built units, based on inhabitants’ needs which could vary over time. Typically, building materials were those available on site, and they were assembled according to an empirical determined “rule of thumb”. Therefore, walls were often made of poor-quality masonry textures,on which timber floors simply rested. Over the centuries, the historical built environment has proved its weakness to seismic events, whose effects were prevented by adopting anti-seismic devices. In a recent past, reinforced concrete (r.c.) replaced those traditional solutions, according to the prescriptions passed in Italy at the end of the 20th century. R.c. structures replaced the original ones, emulating the aspects of vernacular architecture, but resulting in the complete modification of the structure. The paper aims at demonstrating how seismic events can disruptively unveil the hidden traces of tampering and transformations on historical buildings. The 2016 Central Italy earthquake proved the unfavorable effect of r.c. interventions on poor quality walls, as they increased the intrinsic vulnerability of traditional architecture, related to its structural conception. It is essential to identify the effect of some interventions to prevent those dramatic damage scenarios and the irreversible loss of the historical built environment.