Investigations on historic centers in seismic areas: guidelines for the diagnosis

After the earthquake that hit central Italy in 1979, many small historic centers were restored. A subsequent seismic event occurred in 1997 in Umbria-Marche regions revealed that some techniques used in the previous interventions were not successful due to low durability of new materials and/or incompatibility between the new and the existing materials and structures. An extensive investigation on four small typical historic centers in Umbria was carried out. The objectives of the research were: (i) to define a methodology for the vulnerability analysis of historic buildings at the level of the historic centre, (ii) to collect information on the effectiveness of the repair techniques both traditional and new, (iii) to set up Databases storing the information useful to prepare rescue plans, (iv) to use the collected knowledge for the implementation of reliable models for the vulnerability analysis, (v) to prepare guidelines for investigation and vulnerability analysis.