Earthquake-induced environmental impacts for residential Italian buildings: Consequence models and risk assessment

Abstract

The growing interest in built environment sustainability calls for integrating seismic risk into the life cycle analysis of vulnerable structures in earthquake-prone regions. To serve such a need, this study develops consequence models that estimate the environmental impacts stemming from the repair of multiple earthquake-induced damage levels (or damage states, DSs) for typical structural/non-structural components of reinforced concrete (RC) buildings in Italy. These models are compatible with the FEMA P-58 risk assessment framework and are derived from empirical data on various construction materials involved in repair works. The environmental impacts are expressed in terms of embodied carbon, a metric that quantifies greenhouse gas emissions contributing to global warming (and hence climate change). The derived consequence models are adopted within the FEMA P-58 framework to conduct a risk-based assessment of earthquake-induced embodied carbon for nine archetype RC frames with different heights and design-code levels representing various building types within the residential building stock of Italy. This process requires analysing their nonlinear response under increasing ground-shaking intensities, quantifying damage in individual building components, and then converting the damage to embodied carbon using the derived consequence models. Lastly, this study derives building-level (as opposed to component-level) damage-to-embodied carbon ratios, which link the structure-specific global DSs to the corresponding normalised embodied carbon for each case-study frame. These ratios are valuable in risk assessments of building portfolios as they enable rapid estimations of environmental impacts, achieving a trade-off between accuracy and computational time/effort. The correlation between embodied carbon and repair costs is subsequently investigated to explore practical simplifications in risk-based analyses of environmental impacts.