Community-Level Seismic Risk and Retrofitting Portfolios in Developing Countries: Cost-Effective Assessment Framework and Application

Large earthquakes may cause severe damage and catastrophic consequences to communities. In developing countries, despite implementing building codes and construction practices, most buildings remain vulnerable due to precode and nonengineering constructions. Existing seismic risk evaluation approaches heavily focus on estimating physical damages and resulting subsequent, direct economic loss, unable to connect physical system performance to the social system. This study developed an applied framework that enables evaluating potential seismic damage to physical systems and resulting social impacts by connecting physical damage to social systems. Using a scenario-based approach, the proposed framework: (1) evaluates seismic damages to buildings, (2) relates physical damages to socioeconomic consequences in terms of population dislocation, educational impact, and disruption in critical and essential facilities, and (3) generates retrofitting scenarios by incorporating retrofitting actions into fragility curves for retrofitted buildings to support risk mitigation planning. The framework is illustrated for an earthquake-prone city, Sylhet, Bangladesh.