New methodology for urban seismic risk assessment from a holistic perspective

The seismic risk evaluation usually works with a fragmented concept of risk, which depends on the scientific discipline in charge of the assessment. To achieve an effective performance of the risk management, it is necessary to define risk as the potential economic, social and environmental consequences due to a hazardous phenomenon in a period of time. This article presents a methodology which evaluates the seismic risk from a holistic perspective, which means, it takes into account the expected physical damage and also the conditions related to social fragility and lack of resilience, which favour the second order effects when a hazard event strikes an urban centre. This seeks to obtain results which are useful in the decision making process for risk reduction. The proposed method for urban seismic risk evaluation uses the fuzzy sets theory in order to handle qualitative concepts and variables involved in the assessment, the physical risk level and aggravation level, related to the social fragility and the lack of resilience, are evaluated and finally a total risk level is determinate.