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A probabilistic earthquake risk assessment was developed for urban planning and emergency response activities in the landscape unit of 'Pla de Barcelona', Catalonia, Spain. This assessment was developed under an integral territorial management project framework to develop a pilot platform for territorial prediction (plates.cimne.com). Using state-of-the-art methodologies, risk results in different metrics were obtained after assessing the feasible losses on a high-resolution exposure database. Critical earthquake scenarios have been identified to provide emergency and territorial management information to the Department of Vice-presidency, Digital Policies, and territory; of the Generalitat of Catalonia., This research was funded by the Generalitat de Catalunya through the “Projecte de tecnologies digitals avançades (TDA) - Plataforma de Predicció Territorial (PIPLATES)”. The authors also acknowledge the financial support through the Severo Ochoa Centers of Excellence Program (CEX 2018-000797-S) funded by MCIN/AEI/10.13039/501100011033., Objectius de Desenvolupament Sostenible::11 - Ciutats i Comunitats Sostenibles, Postprint (published version)

The final publication is available at Springer via http://dx.doi.org/10.1007%2Fs11069-017-3087-9, Among the activities developed under the framework of the Global Earthquake Model, the development of a global consequences database was included. This was defined with the objective of serving as public repository of damages and losses, occurred on different types of elements because of a selected list of earthquakes with epicentres at varying locations around the globe, but also to be used as a benchmark for the development of vulnerability models that capture specific characteristics of the building typologies in each country. The online earthquakes consequences’ database has information on 71 events where 16 of them occurred in the Latin America and the Caribbean Region. A complete and comprehensive review and data gathering process were developed for these selected earthquakes accounting for different aspects and dimensions that were considered of interest, besides the physical damage, such as casualties, socio-economic implications, damages and disruptions in critical facilities and infrastructures, together with the occurrence of secondary events triggered by the ground shaking such as landslides and tsunamis. When possible, the damage and casualties were geo-located using a standardized approach and included in the database. The contributions of the Latin America and Caribbean Region to the database were at the same time a challenge and an opportunity to collect, review, put together and standardize, up to a certain point, damage data of previous earthquakes additionally of being a step forward in the field of open data., Peer Reviewed, Postprint (author's final draft)

The final publication is available at Springer via http://dx.doi.org/10.1007/s11069-015-2056-4, Medellín is the second largest city of Colombia with more than 2 million inhabitants according to the latest census and with more than 240,000 public and private buildings. It is located on an intermediate seismic hazard area according to the seismic zonation of Colombia although no destructive earthquakes have occurred having as a consequence low seismic risk awareness among its inhabitants. Using the results of a fully probabilistic risk assessment of the city with a building by building resolution level and considering the dynamic soil response, average annual losses by sectors as well as casualties and other direct effects are obtained and aggregated at county level. Using the holistic evaluation module of the multi-hazard risk assessment CAPRA platform, EvHo, a comprehensive assessment that considered the social fragility and lack or resilience at county level is performed making use of a set of indicators with the objective of capturing the aggravating conditions of the initial physical impact. The urban seismic risk index, USRi, is obtained at county level which is useful to communicate risk to decision-makers and stakeholders besides making easy identifying potential zones that can be problematic in terms of several dimensions of the vulnerability. This case study is an example of how a multidisciplinary research on disaster risk reduction helps to show how risk analysis can be of high relevance for decision-making processes in disaster risk management., Peer Reviewed, Postprint (author's final draft)

In many seismic areas of the world, there are nowadays vulnerable structures, designed and built without seismic codes or using outdated codes. The seismic vulnerability of the buildings is, sometimes, not so difficult to be intuited. However, when vulnerability is to be estimated in a numerical way, a coherent conceptual framework and a methodology, not so easy to be developed, is required. Now we are faced with a complex and complicated problem which we have to solve without disregarding the uncertainties inherent to the characteristics of the structures and of the seismic action; therefore, the methods to assess seismic vulnerability and risk require the use of a probabilistic framework. Uncertainties have a pronounced effect on the behaviour of the structures, especially when they enter in the nonlinear range during earthquakes. The effects of the May 2011 Lorca earthquake on the structures of the affected area are used herein as examples of vulnerability evaluation of buildings and to test the capacity of the vulnerability assessment methods. The damages produced in the structures of Lorca by the earthquake, obtained through inspection after the earthquake, are compared herein with those calculated by means of a probabilistic risk analysis., Postprint (published version)

One of the projects of the Global Earthquake Model (GEM) was to develop a global earthquake consequences database (GEMECD) which served both to be an open and public repository of damages and losses on different types of elements at global level and also as a benchmark for the development of vulnerability models that could capture specific characteristics of the affected countries. The online earthquakes consequences database has information on 71 events where 14 correspond to events that occurred within the Latin American and the Caribbean Region. A comprehensive review and data gathering process was developed identifying in each of the selected earthquakes aspects that were of interest in terms of casualties (considering socio-economic implications) assessment, damages to critical facilities and infrastructure and those that triggered secondary hazards such as landslides, tsunami and fires. When possible, damages and casualties were geo-located under the standardized framework of the GEMECD. The contributions of the Latin American and the Caribbean region to the database represented both a challenge and an opportunity to collect, review and standardize data from previous earthquakes besides moving a step forward in the field of open-data., Postprint (published version)

This is an Accepted Manuscript of an article published by Taylor & Francis Group in Human and Ecological Risk Assessment: An International Journal on 2016, available online at: http://www.tandfonline.com/10.1080/10807039.2015.1095072, A methodology to estimate, in a probabilistic way, the annual cost to society of premature deaths because of earthquakes is proposed in this article. The methodology makes use of results obtained by means of prospective and probabilistic seismic risk assessments where expected deaths caused by the collapse of buildings are obtained. Those results, combined with demographic and macroeconomic indicators such as the age distribution, life expectancy at birth, and per capita gross domestic product, are used to estimate the cost to society in terms of lost productivity due to premature mortality because of earthquakes. The proposed methodology does not attempt to estimate nor assign a cost to human lives at any stage, but the one associated to lost productivity at the societal level. One of the descriptors of the methodology is part of the components of the disability adjusted life year, a widely used metric in the public health field that estimates the burden of diseases based mostly on historical data. As an example, the methodology is applied to Medellin, the second largest city of Colombia, finding that the cost of lost productivity due to premature mortality because of earthquakes has a similar order of magnitude to the direct physical losses in the public and private building stock calculated in a previous probabilistic seismic risk assessment., Peer Reviewed, Postprint (author's final draft)

La Asociación Colombiana de Ingeniería Sísmica (AIS) ha realizado una actualización del Código Colombiano de Diseño Sismorresistente para Puentes (CCP-14). Entre las diferentes tareas realizadas, ha establecido el valor de los coeficientes de diseño sismorresistente compatibles con la forma funcional del espectro elástico de diseño seleccionado. Para ello, se ha actualizado la evaluación probabilista de la amenaza sísmica a escala nacional y, a partir de ella, se han calculado dichos coeficientes para todo el territorio nacional. Con respecto al último estudio general de amenaza sísmica de Colombia, se dispone de cinco años más de registros de sismicidad y, por consiguiente, de un mejor entendimiento del entorno sísmico colombiano, lo cual ha permitido realizar actualizaciones relacionadas con los parámetros de sismicidad de las fuentes sismogénicas y utilizar relaciones de atenuación de movimiento fuerte calibradas a partir de registros locales. Se presentan los mapas de zonificación sísmica para los tres coeficientes de diseño incluidos en el CCP-14 así como la herramienta gratuita de visualización en línea de los resultados., Peer Reviewed, Postprint (published version)

A loss and damage assessment was performed for the buildings of Lorca, Spain, considering an earthquake hazard scenario with similar characteristics to those of a real event which occurred on May 11th, 2011, in terms of epicentre, depth and magnitude while also considering the local soil response. This low-to moderate earthquake caused severe damage and disruption in the region and especially on the city. A building by building resolution database was developed and used for damage and loss assessment. The portfolio of buildings was characterized by means of indexes capturing information from a structural point of view such as age, main construction materials, number of stories, and building class as well as others related to age and vulnerability classes. A replacement cost approach was selected for the analysis in order to calculate the direct losses incurred by the event. Seismic hazard and vulnerability were modelled in a probabilistic way, considering their inherent uncertainties which were also taken into account in the damage and loss calculation process. Losses have been expressed in terms of the mean damage ratio of each dwelling and since the analysis has been performed on a geographical information system platform, the distribution of the damage and its categories was mapped for the entire urban centre. The simulated damages and losses were compared with the observed ones reported by the local authorities and institutions that inspected the city after the event., Peer Reviewed, Postprint (author's final draft)

En este artículo se ha realizado una evaluación probabilista e integral del riesgo sísmico para las edificaciones de Lorca, la ciudad más afectada tras el sismo de mayo de 2011 en la Región de Murcia, España. La amenaza sísmica se ha representado mediante un conjunto de escenarios estocásticos que permite considerar el efecto de eventos pequeños, moderados y extremos en las posibles pérdidas futuras. Mediante funciones de transferencia espectrales, se ha considerado la respuesta dinámica del suelo. Se ha utilizado una base de datos de elementos expuestos con nivel de resolución edificio por edificio, la cual permite la desagregación de los resultados en diferentes categorías y, además, la obtención de mapas de riesgo sísmico para la visualización de la distribución geográfica de las pérdidas futuras. Para cada una de las tipologías estructurales identificadas se ha asignado una función de vulnerabilidad que permite obtener las pérdidas esperadas para diferentes niveles de aceleración. Los resultados de riesgo se han obtenido en forma de curva de excedencia de pérdidas a partir de la cual pueden derivarse otras métricas probabilistas de riesgo como la pérdida anual esperada y la pérdida máxima probable. Los resultados de riesgo resultan útiles para los tomadores de decisiones en ámbitos de planeación de emergencia, desarrollo de planes de refuerzo de edificaciones existentes y protección financiera mediante mecanismos tradicionales de seguro y reaseguro u otros instrumentos alternativos para la transferencia del riesgo., A comprehensive and probabilistic seismic risk assessment has been performed for the buildings of Lorca, the most affected city in the region of Murcia, Spain, after the May 2011 earthquake. Seismic hazard is represented through a set of stochastic scenarios that allow accounting for small, moderate and extreme events in the future losses, also through spectral transfer functions the dynamic soil response has been considered. A building by building resolution level database has been used allowing the disaggregation of risk results in several categories besides allowing the generation of risk maps to visualize the geographical distribution of the future losses. For each of the identified building classes a vulnerability function has been assigned to determine the expected losses for different acceleration levels. Risk results have been obtained in terms of the loss exceedance curve from where other probabilistic risk metrics such as the average annual loss and the probable maximum loss can be derived. Risk results are useful for the decision-makers in the fields of emergency planning, existent building retrofitting schemes and financial protection through traditional insurance and reinsurance schemes or with alternative risk transfer instruments., Peer Reviewed, Postprint (published version)

Postprint (published version)

A numerical procedure for the calibration of a source spectrum model to find the optimal combination of seismological parameters and derive unbiased ground motion prediction equations is presented, using available accelerogram recordings as calibration target. The source spectrum model is used to compute the radiated spectra of SH- waves for different seismic moments and hypocentral distances, combining point (far field) and finite (near field) source models. The expected value of the peak ground acceleration is computed from the radiated spectra using random vibrations theory. A genetic algorithm is used to search for the source spectrum parameters that best fit the available strong motion recordings. The procedure can be applied to any region with statistically significant accelerogram records. The proposed methodology is followed to derive spectral ground motion prediction equations compatible with the seismotectonic environment of Colombia, using 206 strong motion recordings as the calibration target. The obtained ground motion prediction equations are compared with those used in the latest national seismic hazard assessment study of Colombia. The comparison shows that the strong ground motion prediction equations obtained using the proposed methodology have lower residual bias, showing reasonable matching between them and the real strong motion recordings., Postprint (published version)

A loss assessment was performed for the buildings of Lorca, Spain, considering an earthquake hazard scenario with similar characteristics to those of the real event which occurred on May 11th 2011, in terms of epicentre, depth and magnitude. This low-to moderate earthquake caused severe damage and disruption in the region and especially on the city. A building by building resolution database was developed and used for damage and loss assessment. The portfolio of buildings was characterized by means of relevant indexes capturing information from a structural point of view such as age, main construction materials, number of stories, and building class. A replacement cost approach was selected for the analysis in order to calculate the direct losses incurred by the event. Hazard and vulnerability were modelled in a probabilistic way, considering their inherent uncertainties which were also taken into account in the damage and loss calculation process. Losses have been expressed in terms of the mean damage ratio of each dwelling and since the analysis has been performed on a geographical information system platform, the distribution of the damage and its categories was mapped for the entire urban centre. The simulated damage was compared with the observed damage reported by the local authorities that inspected the city after the event., Postprint (published version)

En el marco del Global Assessment Report on Disaster Risk Reduction 2013, preparado por la Oficina de las Naciones Unidas para la Reducción del Riesgo de Desastres (UNISDR), se llevó a cabo, por primera vez, un estudio probabilista de peligro sísmico a nivel global, usando los mismos métodos para todo el Globo. A partir de sus resultados fue posible obtener un conjunto estocástico de escenarios para diferentes intensidades sísmicas (aceleraciones espectrales, 5% del amortiguamiento crítico), que a su vez fueron usados en un estudio de riesgo sísmico completamente probabilista. Primero, el Globo se dividió en un conjunto de áreas sismogenéticas, a cada una de las cuales se asignó una magnitud máxima y un régimen tectónico predominante. Se supuso que la sismicidad de cada región quedaba correctamente definida utilizando una relación magnitud-frecuencia del tipo Gutenberg-Richter, cuyos valores a y b fueron obtenidos usando un procedimiento de sismicidad suavizada basada en el catálogo sísmico NEIC-USGS. Este catálogo fue previamente sometido a un proceso de remoción de réplicas y verificación de completez para varios valores de magnitud umbral. A partir del régimen tectónico predominante asignado a cada región, se le asignó una relación de atenuación. Los cálculos probabilistas de peligro sísmico se llevaron a cabo con el programa CRISIS2014, el cual generó curvas convencionales de peligro sísmico para diferentes intensidades, y mapas de aceleraciones asociadas a varios periodos de retorno; adicionalmente, CRISIS generó un conjunto de escenarios estocásticos compatibles con la plataforma CAPRA. Estos escenarios fueron usados para llevar a cabo un análisis probabilista grueso de riesgo sísmico para todo el mundo., Peer Reviewed, Postprint (published version)

En el marco de la actualización del Código Colombiano de Puentes, el Comité AIS-300 ha realizado una evaluación de la amenaza sísmica en roca a nivel nacional utilizando información actualizada con respecto al Estudio General de Amenaza Sísmica realizado para el Reglamento NSR-10, en términos del catálogo utilizado, con 5 años más de información y las relaciones de atenuación de movimiento fuerte, calibradas a partir de registros locales. Para la presente actualización se ha evaluado la amenaza sísmica con un enfoque probabilista y espectral con el objetivo de establecer los valores de los coeficientes sísmicos de diseño, denominados ahora como PGA, Ss y S1, asociados, en esta ocasión, a una probabilidad de excedencia del 7% en 75 años, lo que equivale, aproximadamente, a un período de retorno promedio de 975 años., Peer Reviewed, Postprint (published version)

An analysis of the earthquake losses for Lorca, Spain has been performed in this article. The seismic hazard is represented by a set of stochastic scenarios that allow considering the effect of all the possible events upon the future losses in the city. The dynamic response of the soil has been also considered using spectral transfer functions. Another important starting point for estimating damages and losses has been the database of the buildings of Lorca which includes essential information regarding the structures such as age, building materials, number of floors and typology. To each structural type, vulnerability functions have been associated in order to obtain the expected losses for different levels of the ground acceleration. An approach based on the replacement cost allows calculating direct losses in monetary terms. The most important result was the loss exceedance curve from which the expected annual loss and the probable maximum loss are derived. Both the threat and vulnerability were modeled in a probabilistic way, considering their inherent uncertainties and also their propagation in the damages and losses calculation process., Postprint (published version)

Se actualizó la microzonificación sísmica de Manizales mediante la aplicación de una metodología moderna para la evaluación de efectos de sitio en ciudades, la cual está basada en la geometría de las formaciones geológicas conformadas por suelos blandos. Sobre la base de la interpretación geológica para el área de la ciudad, la elevación (sobre el nivel del mar) de los contactos geológicos es definida, y se obtiene un modelo geométrico tridimensional del subsuelo de la ciudad. La información geotécnica disponible se utiliza para asignar tipos de suelo al modelo geométrico. Las características estáticas y dinámicas del suelo se definen como variables aleatorias y sus momentos de probabilidad se calculan mediante estadística sobre los datos geotécnicos disponibles. Una malla de cálculo compuesta por 1275 nodos se define sobre la ciudad y para cada nodo se obtiene una estratigrafía sintética con parámetros geotécnicos asignados siguiendo sus distribuciones de probabilidad. La respuesta dinámica se calcula, para cada nodo de la malla, por medio de un análisis 1D no lineal (lineal equivalente), utilizando un conjunto de espectros de amplitudes de Fourier generados a nivel de roca firme mediante un modelo de espectro de fuente, para diferentes combinaciones de magnitud y distancia. De esta manera se definen funciones de atenuación del movimiento fuerte específicas de cada nodo de la malla de cálculo. Se calcula la amenaza sísmica a nivel de superficie del terreno y se obtienen los espectros de amenaza uniforme para 475 años de periodo de retorno. A partir de dichos espectros se ajustan espectros de diseño armonizados a la NSR 10, mediante la búsqueda aleatoria de los parámetros Fa y Fv que garantizan un ajuste óptimo. Se calculó la amenaza a nivel de roca firme para establecer los valores de los parámetros Aa y Av. De esta manera, para cualquier ubicación dentro de la ciudad, es posible establecer los valores para determinar el espectro de diseño adecuado. Los resultados, Peer Reviewed, Postprint (published version)

El Modelo Global del Riesgo (MGR), que se desarrolló inicialmente para el GAR13 y que ahora ha sido actualizado para GAR15, incorpora los componentes pertinentes para la evaluación del riesgo catastrófico: los elementos o bienes expuestos, el nivel de amenaza que les afecta y su vulnerabilidad frente a dicha amenaza. El principal resultado de la MGR es la curva nacional de excedencia de pérdidas (CEP) para cada país, que es una medida que representa la frecuencia anual en que una pérdida económica determinada puede superarse en el futuro. Se calcularon métricas tales como la pérdida anual esperada (PAE) y la Pérdida Máxima (PMP) de 216 países, derivando estas métricas directamente de la CEP de cada país. La PAE es la medida más robusta de riesgo, siendo una medida probabilística compacta, relativamente insensible a la incertidumbre. Esta métrica se calcula de la suma del producto de las pérdidas previstas de cada evento con la frecuencia anual de ocurrencia del mismo evento, suponiendo un proceso estacionario y exhaustivo de eventos (es decir, se consideran todos los eventos posibles). Además, la pérdida anual esperada puede ser expresada como una fracción del valor expuesto. Esta métrica versátil es conocida en la industria de seguros como la, Peer Reviewed, Postprint (published version)

De acuerdo al Reglamento NSR-10 las ciudades de Bogotá y Medellín tienen los mismos coeficientes de diseño Aa y Av que desde una primera lectura, indicarían el mismo nivel de amenaza sísmica. Sin embargo, la selección del período de retorno para diseño sismo resistente corresponde a una decisión arbitraria y valores iguales en ambas ciudades corresponden a una mera coincidencia dado que la amenaza sísmica en cada caso se ve influenciada por entornos sismo-tectónicos totalmente diferentes. La comparación de los resultados de riesgo sísmico desde el punto de vista físico de ambas ciudades utilizando la misma metodología, permite identificar la influencia de las fuentes sismogénicas, los efectos de sitio y la vulnerabilidad física en dichos análisis.

La nueva interpretación tectónica que propone la existencia de una falla denominada Caldas Tear ha motivado una evaluación de amenaza sísmica a nivel nacional, usando la misma metodología e información del estudio de amenaza sísmica actualizado para el Reglamento NSR-10.Con ambos resultados, se realiza la evaluación de riesgo sísmico de Bogotá y Manizales obteniendo la curva de excedencia de pérdidas, pérdidas máximas probables y la pérdida anual esperada. En la estimación de las pérdidas de las edificaciones de ambas ciudades, se consideran las microzonificaciones. La comparación permite observar la disminución y aumento del riesgo sísmico en Bogotá y Manizales respectivamente.