Técnicas innovadoras para la evaluación del riesgo sísmico y su gestión en centros urbanos: Acciones ex ante y ex post

Abstract

The objectives of this thesis are: the ex ante seismic risk evaluation for urban centers, the disaster risk management evaluation and the ex post risk evaluation of the damaged buildings after an earthquake. A complete review of the basic concepts and of the most important recent works performed in these fields. These aspects are basic for the development of the new ex ante and ex post seismic risk evaluation approaches which are proposed in this thesis and for the s evaluation of the effectiveness of the disaster risk management.<br/>Risk has been defined, for management purposes, as the potential economic, social and environmental consequences of hazardous events that may occur in a specified period of time. In Chapter 3 of this thesis, 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, which favour the second order effects when a hazard event strikes an urban centre. The proposed general urban risk evaluation method is multi-hazard and holistic, that is, an integrated and comprehensive approach whose objective is to guide decision-making. This method has been applied to the cities of Bogota, Colombia, and Barcelona, Spain, and it is being applied to Metro Manila, Philippines.<br/>Chapter 4 develops a methodology for the disaster risk management evaluation. A disaster risk management index, DRMi, is conceptually supported and formulated, which measures the performance and the effectiveness of the risk management in a territory that can be a country, a subnational region or a city. The proposed DRMi is developed by quantifying four public policies: the risk identification, the risk reduction, the disaster management and the governance and financial protection. With this methodology eleven countries of Latin America and the Caribbean; Colombia at subnational level and Bogota at urban level were evaluated.<br/>In chapter 5 a methodology for the ex-post evaluation of the seismic damage is developed, using computational intelligence techniques. It has the objective of assisting non-expert professionals of building construction in evaluating the damage and safety of buildings after strong earthquakes, facilitating decision-making on their habitability and reparability during the emergency response phase. This neuro-fuzzy system has been adopted for its official use by the cities of Bogota and Manizales, in Colombia.<br/>The conclusions of this thesis are shown in Chapter 6, where also future lines of investigation are presented. The main conclusions are:<br/>- The proposed model for the holistic evaluation of the seismic risk facilitates the integral risk management and the decision making on risk reduction. The analysis of the results allows to establish priorities for the mitigation and actions of prevention and planning aiming to modify the conditions that influence on the risk of the zone.<br/>- The proposed disaster risk management index, DRMi, is consistent, methodical and has been developed to measure the risk management performance. This index allows to make the evaluation in a systematic and quantitative way and allows to define operation objectives and to improve the efficiency of the risk management. <br/>- A novel system of support to the habitability and damage evaluation of buildings, based on fuzzy logic and artificial neural networks was proposed. This kind of tool is useful due to the type of information that is handled, which is subjective and incomplete. Linguistic qualifications can appropriately be represented by fuzzy sets. An artificial neuronal network was used to calibrate the system starting from the experts judgment.<br/><br/>Finally, several annexes are included which include details on methodological and calculation aspects related to the of proposed risk evaluation methods.