Multi-scale and multi-refinement framework for seismic risk assessment of urban areas

As a part of a wider research project, this paper aims to develop an innovative framework for seismic risk assessment of urban areas. The investigated procedure employs a multi-scale approach, from individual elements (e.g., single buildings, water pipelines), to various clusters and interconnected layers and, finally, the entire urban area. The last one is represented by a multilayered model, including the “building stock” and the utilities layers (e.g. water distribution networks). Moreover, a key feature relies on a multi-refinement level framework, which allows for the evaluation of loss metrics even in the case of limited knowledge. Alternative refinement levels involve: i) typological-based vulnerability assessment; ii) analytical/mechanical procedures, and iii) numerical (software-based) simulations. The uncertainties for each refinement level are assessed and propagated. The paper also discusses preliminary results for the building stock and water utilities. Implementing such a framework in a City Digital Twin environment can enhance the awareness of stakeholders and the general population towards seismic risk prompting decision-makers in taking action.