Small centres damaged by 2009 L'Aquila earthquake: on site analyses of historical masonry aggregates

This paper is focused on the illustration of on site works developed on some historical centres struck by L'Aquila earthquake of April 6, 2009 starting from the first emergency phase. The large number of minor historical centres damaged and the highly differentiated level of damage occurred implied the need of different procedures to study them. The common goal of all these studies is to illustrate the variability of the seismic response of historical masonry buildings trying to identify both the causes that have increased the damage (vulnerabilities) and the factors that have limited or prevented it (strengths). The preliminary results allow to formulate a first evaluation in view of drawing up reconstruction plans.