To support urban emergency planning: A GIS instrument for the choice of optimal routes based on seismic hazards

Starting from the awareness that emergency management cannot be conducted in a rigid and systematic way as it is often linked to the factor of event unpredictability, however, the need to create a collective language and culture, aiming at common goals allowing organizations and communities to prepare themselves appropriately for different types of emergency, emerges, both locally and internationally (Alexander, 2016). With reference to this, the authors propose three planning phases connected to a local experimentation, but one which is transferable to any territorial context, to be regulated through the definition of "general" guidelines, with the precise aim of avoiding the free construction and interpretation of information. Within these guidelines we also seek to define technical specifications that can support planners in the design of emergency plans. In particular, the contribution refers to the definition of a methodology aimed at the need to address one of the most relevant problems that may occur in the case of a seismic event, namely the impossibility of reaching the affected places due to the inaccessibility of pre-established routes which have been obstructed by collapses caused by the earthquake. This methodology, through the use of a GIS platform, could allow, on the one hand, the planning of optimal connections in the case of limit conditions, and on the other hand, it could allow the identification and planning of safety interventions, assigning appropriate priorities to various buildings, not only on the basis of their relevance compared to road use, but also on the basis of cost considerations.