Sustainable planning of seismic emergency in historic centres through semeiotic tools: Comparison of different existing methods through real case studies

Sustainable cities have to constantly face natural catastrophes, and planning actions should be oriented to quickly manage emergency conditions. Earthquake represents one of the most critical disasters. Earthquake-induced built environment modifications (i.e. building debris) affect the urban paths network availability. Historic centres are relevant scenarios because of their specific features (i.e. Heritage vulnerability; complex and compact fabric). Predicting which paths could be used by rescuers to rapidly reach damaged inhabitants could reduce losses and improve first aid actions. Sustainable semeiotic tools are proposed to quickly esteem the paths availability combining street geometrical features and building damages. Currently, no study provides insights on methods reliability. Hence, this work critically analyses methods outcomes by implementing them, for the first time, on the same real-world sample (Italian historic centres). Rapid tools (satellite images, photographic documentation) are used to compare methods previsions with effective post-earthquake paths availability. Pros and cons of each analysed method are evidenced, underlining that the approach that combines street-building geometry, building vulnerability and earthquake severity seems to give the best results. This could help Local Authorities and Civil Protection Bodies in better developing risk-mitigation strategies concerning, e.g., emergency management (rescuers’ access routes definition) and urban planning (building retrofitting interventions).