Historical centers in seismic area: methodology for conservation, prevention and reconstruction. The case study of Villa Sant’Angelo

In recent times, the recurrence of seismic events has suggested again to pay careful attention to the ways to intervene on the existing buildings whit the aim of increase their security requirements together with maintaining high levels in urban quality. In particular, it is a shared opinion that the conservation of historical city, especially in earthquake affected areas, should take into proper consideration the theme of seismic security. Nevertheless, this particular topic is confronted to operating methods which are still confused and often ineffective. This paper describes a methodology for the analysis of building aggregates of historical city, aimed at reducing their susceptibility to earthquake induced damage. This methodology has been applied to a block in the historical center of Villa Sant'Angelo, one of the towns near L'Aquila affected by the seismic event occurred in April 2009. The aim is to show that, even in situations of so high seismic risk, the deep knowledge of building constructions and of their environment is a basic condition in order to find operating solutions based on sustainability and cost saving principles. In this way, the restoration projects which spring from these principles, can find a good alternative to the easier but less sustainable solution of city delocalization. The methodology here proposed can be applied both in post-earthquake rebuild conditions and in the most advantageous prevention activities. In a period of so hard economic crisis, the lesson learned from last earthquakes imposes us to move our resources from emergency to prevention activities.