Abstract

The earthquake is a serious risk factor for archaeological heritage and, especially in this thematic area, the preventive protection assumes a strategic importance due to the lack of purpose that a reconstructive intervention would produce. However, the multiple problems of conservation and enhancement of the archeological heritage make the planning of damage mitigation complex, according to the criteria adopted for historical architecture. From the evolutionary framework of the sectoral regulations in Italy emerges a generic extension of the provisions for specific architectural monuments to the archaeological ones, in which the absence of connections or their intrinsic weakness, if any, increases their vulnerability. Currently, it is clear that the absence of a specific "functional connotation" of ruins, apart from the visit one, places these contexts on the margin of the most recent regulations reconsiderations. Indeed, the current Linee Guida Mibact 2011 (Mibact Guidelines 2011) introduce a rapid evaluation methodology on a territorial scale (LV1) which does not consider the archaeological structures. The paper proposes a rapid assessment method for the archaeological seismic vulnerability, which tries to connect the knowledge system with the analytical result on a territorial scale. This approach, based on a hierarchical system identification of structural 'morphos-types', is developed with applications conducted on the Roman Forum structures. Specifically, the attention is focused on the ruins constituted by walls without connections, whose structural behaviour, far from the global one, can be assimilated to a 'macro-element'. The seismic risk assessment is set according to the Carta del Rischio (the Risk Map) system methodology. This method introduces an algorithm for calculating structural vulnerability able to grasp the constructive and conservative specificities that influence the structural behaviour of the archaeological pre-existences.