Urban morphology in support of disaster risk reduction: toward theory and methods for a spatial approach to tackling urban vulnerability to earthquakes

Among the most recent directions of urban morphology research is its integration with disaster studies, in support of disaster risk reduction (DRR) efforts at the urban scale. Yet, the built and unbuilt components of urban form are still disproportionately investigated for DRR purposes, with predominant approaches centred on buildings leaving the DRR potential of the urban spatial network relatively under-investigated. This paper, at the intersection of urban morphology and disaster studies, is the first of a series looking at the spatial component of urban form through the lens of risk, with a focus on urban vulnerability to earthquakes. After discussing how the interplay of configuration, governance, and use of space impact urban disaster risk in earthquake-prone
settlements, the paper introduces a method for the exposure assessment of urban spatial layout. The method, applied on the configurational analysis of four settlements hit by the 2016 Central Italy Earthquakes, associates disaster risk variables to the urban spatial network’s core elements. It develops (i) a theoretical re-definition of the significant disaster risk variables in relation to configurational measures; and (ii) an integrated spatial analysis workflow for visualisation and classification of street segments and routes based on their degree of exposure, to inform both ordinary and emergency planning. In (i), the spatial-configurational dimensions of disaster concepts (hazard, exposure) are identified to unfold the spatial potential in DRR. In (ii), the spatial analysis workflow builds upon the recently developed applications of space syntax angular segment analysis on OSM RCL network, by combining Volunteered Geographic Information (VGI) with land use and disaster-related datasets, to generate hybrid exposure segment maps within the ArcGIS environment. The paper provides a twofold contribution : recontextualization and incorporation of space syntax theoretical knowledge into DRR, and innovative employ of existing applications for multidisciplinary and comprehensive approach to urban vulnerability assessment.