Holistic Urban Seismic Risk Evaluation of Megacities: Application and Robustness

Abstract

From a holistic perspective, disaster risk requires a multidisciplinary evaluation that takes into account not only the expected physical damage, the number and type of casualties or economic losses, but also the conditions related to social fragility and lack of resilience conditions, which favor the second order effects when a hazard event strikes an urban center. In this chapter, the urban risk is evaluated using composite indicators or indices. Expected building damage and losses in the infrastructure, obtained from loss scenarios are basic information for the evaluation of the physical risk index in each unit of analysis. The holistic evaluation of disaster risk is achieved affecting the physical risk with an impact factor, obtained from contextual conditions, such as the socioeconomic fragility and the lack of resilience, that aggravate the physical risk. Available data about these conditions at urban level are necessary to apply the method. The model is explained and the benefits of this approach are illustrated, inviting to the risk management of urban centers.