Barbat Barbat, Horia Alejandro
Total activity: 701
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University professor
Doctoral courses
Doctor Ingeniero
Doctor Ingeniero de Caminos, Canales y Puertos
University degree
Ingeniero Civil
Ingeniero de Caminos Canales y Puertos
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(MC)2 - Group of Computational Mechanics on Continuous Medium
Department
Department of Strength of Materials and Structural Engineering
School
Barcelona School of Civil Engineering (ETSECCPB)
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CIMNE. Centre Internacional de Mètodes Numèrics en Enginyeria Open in new window
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alex.barbatupc.edu
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1 to 50 of 701 results
  • Método numérico para la evaluación holística del riesgo sísmico utilizando la teoría de conjuntos difusos

     Carreño Tibaduiza, Martha Liliana; Barbat Barbat, Horia Alejandro; Cardona, Omar Darío
    Revista internacional de métodos numéricos para cálculo y diseño en ingeniería
    Date of publication: 2014-01-07
    Journal article

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    La teoría de conjuntos difusos ofrece un puente entre el procesamiento simbólico y el numérico que permite el uso de conceptos cualitativos útiles en el proceso de toma de decisiones relacionadas con la gestión del riesgo sísmico y, en general, con la gestión del riesgo de desastres. Su utilización en la evaluación del riesgo sísmico es necesaria en el caso en que los datos para aplicar un método de evaluación convencional del riesgo no estén disponibles o sean insuficientes. Una posible solución, considerada en este artículo, consiste en sustituir la información que falta por la opinión de expertos y en procesar las variables cualitativas y las calificaciones lingüísticas que se obtengan de dichas opiniones en lugar de valores numéricos. El procesamiento se realiza utilizando la teoría de conjuntos difusos. Para lograr una gestión eficaz, el riesgo se debe definir como las posibles consecuencias físicas, económicas, sociales y ambientales que pueden ocurrir en un período de tiempo determinado debido a fenómenos peligrosos. Desde esta perspectiva holística, y utilizando la teoría de conjuntos difusos, el método numérico propuesto calcula un nivel de riesgo físico y un nivel de agravamiento relacionado con las condiciones de fragilidad social y falta de resiliencia, para determinar un nivel de riesgo total. En el artículo se incluyen 2 ejemplos de aplicación del método propuesto y los resultados obtenidos se comparan con los correspondientes a un método convencional de evaluación holística.

  • Framing vulnerability, risk and societal responses: the MOVE framework

     Birkmann, Joern; Cardona, Omar Darío; Carreño Tibaduiza, Martha Liliana; Barbat Barbat, Horia Alejandro; Pelling, Mark; Schneiderbauer, Stefan; Kienberger, Stefan; Keiler, Margreth; Zeil, P.; Welle, T.
    Natural hazards
    Date of publication: 2013-06
    Journal article

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    The paper deals with the development of a general as well as integrative and holistic framework to systematize and assess vulnerability, risk and adaptation. The framework is a thinking tool meant as a heuristic that outlines key factors and different dimensions that need to be addressed when assessing vulnerability in the context of natural hazards and climate change. The approach underlines that the key factors of such a common framework are related to the exposure of a society or system to a hazard or stressor, the susceptibility of the system or community exposed, and its resilience and adaptive capacity. Additionally, it underlines the necessity to consider key factors and multiple thematic dimensions when assessing vulnerability in the context of natural and socio-natural hazards. In this regard, it shows key linkages between the different concepts used within the disaster risk management (DRM) and climate change adaptation (CCA) research. Further, it helps to illustrate the strong relationships between different concepts used in DRM and CCA. The framework is also a tool for communicating complexity and stresses the need for societal change in order to reduce risk and to promote adaptation. With regard to this, the policy relevance of the framework and first results of its application are outlined. Overall, the framework presented enhances the discussion on how to frame and link vulnerability, disaster risk, risk management and adaptation concepts.

  • Probabilistic assessment of the capacity, fragility and seismic damage of reinforced concrete buildings

     Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Hurtado Gomez, Jorge Eduardo
    Revista internacional de métodos numéricos para cálculo y diseño en ingeniería
    Date of publication: 2013-04
    Journal article

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    Currently, many structures existing in seismic areas are highly vulnerable because they have been built without the use of seismic design codes or by using outdated codes. Often, methods for assessing the vulnerability of the structures do not take into account that their seismic behavior is dynamic and highly nonlinear and, moreover, that the structural characteristics and action have large uncertainties. This article aims to assess the vulnerability of structures taking into account that the mechanical properties of materials and the seismic action are random variables, by using advanced techniques based on the Monte Carlo method and on the nonlinear stochastic dynamics. The results obtained with these techniques are compared with those corresponding to a standard vulnerability assessment, based on deterministic models, in order to highlight the differences between both approaches. The main conclusion of this work is the need to address the vulnerability assessment problem from a probabilistic perspective which, combined with advanced nonlinear static and dynamic structural analysis techniques, provides a powerful tool giving information impossible to be captured by means of deterministic models. Finally, detailed results obtained for a building with waffle slabs, which is a structural typology widely used in Spain, are included and discussed. Actualmente en las zonas sísmicas existen estructuras altamente vulnerables, puesto que han sido construidas sin seguir las especificaciones de normas de diseño sismorresistente o siguiendo normas obsoletas. Muchas veces los métodos para evaluar la vulnerabilidad de las estructuras no tienen en cuenta que su comportamiento sísmico es dinámico y fuertemente no lineal y que, además, las características estructurales y de la acción tienen grandes incertidumbres. En este artículo se propone evaluar la vulnerabilidad de las estructuras, considerando que las propiedades mecánicas de los materiales y la acción sísmica son variables aleatorias, mediante técnicas avanzadas con base en el método de Monte Carlo y en la dinámica estocástica no lineal. Los resultados obtenidos con estas técnicas se comparan con los correspondientes a una evaluación de vulnerabilidad estándar, que utiliza modelos deterministas, a fin de resaltar las diferencias entre los 2 enfoques. La principal conclusión de este trabajo es que existe una necesidad de abordar el problema de la evaluación de la vulnerabilidad de estructuras desde una perspectiva probabilista que, al ser combinada con técnicas avanzadas de análisis del comportamiento estructural no lineal estático y dinámico, proporciona una poderosa herramienta que permite obtener información imposible de conseguir mediante modelos deterministas. Se incluyen resultados detallados obtenidos sobre un edificio con forjados reticulares, que es una tipología estructural muy utilizada en España.

  • Methodology and applications for the benefit cost analysis of the seismic risk reduction in building portfolios at broadscale

     Valcarcel Torres, Jairo Andrés; Mora Cuevas, Miguel; Cardona, Omar Darío; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Bernal Granados, Gabriel Andres
    Natural hazards
    Date of publication: 2013-10-01
    Journal article

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    This article presents a methodology for an estimate of the benefit cost ratio of the seismic risk reduction in buildings portfolio at broadscale, for a world region, allowing comparing the results obtained for the countries belonging to that region. This methodology encompasses (1) the generation of a set of random seismic events and the evaluation of the spectral accelerations at the buildings location; (2) the estimation of the buildings built area, the economic value, as well as the classification in structural typologies; (3) the development of vulnerability curves for each typology; (4) the estimation of the annual average loss of the buildings portfolio in the current conditions as well as in the case of a hypothetical structural intervention. The benefit cost ratio is estimated as the difference between the estimates of the present value of these two annual average losses, divided by the retrofitting costs. This methodology has been applied to the portfolio of public schools of 14 countries of Latin America and the Caribbean, for evaluating the feasibility of the seismic risk reduction at a national scale. © 2013 Springer Science+Business Media Dordrecht.

  • Indicadores de amenaza, exposición y riesgo urbano

     Carreño Tibaduiza, Martha Liliana; Barbat Barbat, Horia Alejandro; Marulanda Fraume, Mabel Cristina
    Date of publication: 2013-03-06
    Book chapter

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  • Incremental dynamic analysis and pushover analysis of buildings: a probabilistic comparison

     Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Hurtado Gomez, Jorge Eduardo
    Date of publication: 2013-03-05
    Book chapter

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    The considerable influence of inherent uncertainties on structural behavior has led the engineering community to recognize the importance of a stochastic approach to structural problems. Issues related to uncertainty quantification and its influence on the reliability of the computational models are continuously gaining in significance. In particular, the problems of dynamic response analysis and reliability assessment of structures with uncertain system and excitation parameters have been the subject of continuous research over the last two decades as a result of the increasing availability of powerful computing resources and technology. This book is a follow up of a previous book with the same subject (ISBN 978-90-481-9986-0) and focuses on advanced computational methods and software tools which can highly assist in tackling complex problems in stochastic dynamic/seismic analysis and design of structures. The selected chapters are authored by some of the most active scholars in their respective areas and represent some of the most recent developments in this field. The book consists of 21 chapters which can be grouped into several thematic topics including dynamic analysis of stochastic systems, reliability-based design, structural control and health monitoring, model updating, system identification, wave propagation in random media, seismic fragility analysis and damage assessment. This edited book is primarily intended for researchers and post-graduate students who are familiar with the fundamentals and wish to study or to advance the state of the art on a particular topic in the field of computational stochastic structural dynamics. Nevertheless, practicing engineers could benefit as well from it as most code provisions tend to incorporate probabilistic concepts in the analysis and design of structures.

  • Seismic evaluation of low rise RC framed building designed according to Venezuelan codes

     Vielma Pérez, Juan Carlos; Barbat Barbat, Horia Alejandro; Ugel Garrido, Ronald David; Herrera González, Reyes Indira
    Date of publication: 2013-04-09
    Book chapter

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    The mitigation of earthquake-related hazards represents a key role in the modern society. The mitigation of such kind of hazards spans from detailed studies on seismicity, evaluation of site effects, and seismo-induced landslides, tsunamis as well as and the design and analysis of structures to resist such actions. The study of earthquakes ties together science, technology and expertise in infrastructure and engineering in an effort to minimize human and material losses when they inevitably occur. Chapters deal with different topics aiming to mitigate geo-hazards such as: Seismic hazard analysis, Ground investigation for seismic design, Seismic design, assessment and remediation, Earthquake site response analysis and soil-structure interaction analysis.

  • Analysis of ultra low cycle fatigue problems with the Barcelona plastic damage model

     Martinez Garcia, Xavier; Oller Martinez, Sergio Horacio; Barbu, Lucia Gratiela; Barbat Barbat, Horia Alejandro
    International Conference on Computational Plasticity Fundamentals and Applications
    Presentation's date: 2013-09-05
    Presentation of work at congresses

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  • Evaluación probabilista del riesgo sísmico de edificios de hormigón armado con base en la degradación de la rigidez

     Barbat Barbat, Horia Alejandro; Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Hurtado Gomez, Jorge Eduardo
    Congreso Nacional de Ingeniería Sísmica, Colombia
    Presentation's date: 2013-05-29
    Presentation of work at congresses

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    The incremental dynamic analysis is a powerful tool for evaluating the seismic vulnerability and risk of buildings. It allows calculating the global damage of structures for different peak ground accelerations, PGA, and representing this result by means of damage curves. Such curves are currently used to obtain seismic risk scenarios at urban level. Even if the application of this method in a probabilistic environment requires a relevant computational effort, it is the reference method for determining those curves. Nevertheless, it would be of high practical interest to have a simpler method based, for instance, on pushover analysis, for assessing the seismic vulnerability and risk of buildings, which allows obtaining results similar to those based on the incremental dynamic analysis. Referring to the capacity-spectrum-based-methods, expert opinions have been used in previous researches for defining damage states thresholds starting from the yielding and the ultimate spectral displacement identified in the bilinear capacity spectrum. But we prove in this article that the results provided by these methods do not reproduce with sufficient precision the dynamic ones. Therefore, a new procedure for defining the damage states thresholds, based on the stiffness degradation of reinforced concrete building, is proposed herein and a fully probabilistic approach is tackled by means of Monte Carlo simulations. It is demonstrated in the paper that the obtained results are in good agreement with those calculated using the incremental dynamic analysis.

  • Risk assessment of reinforced concrete buildings considering the earthquake directionality effects

     Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Hurtado Gomez, Jorge Eduardo
    Computational Methods in Structural Dynamics and Earthquake Engineering
    Presentation's date: 2013-06-12
    Presentation of work at congresses

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    In order to assess the seismic risk of structures, several methods based on pushover analysis have been developed. These methods are very useful in the case of symmetric structures because they can be easily approximated by means of a 2D model. In the case of asymmetric structures several improvements to the pushover analysis procedure have been proposed for considering the effect of asymmetry on the global response. However, such methods, in some cases, can be more expensive, from computational point of view, than the nonlinear dynamic analysis. In this article, we propose to assess the effect of the directionality of the earthquake by using non-linear dynamic analysis and considering uncertainties in the mechanical properties of the materials and in the seismic action. We use as a case study a group of reinforced concrete buildings located in Lorca, Spain, damaged by the earthquake of May 2011. The results show a good agreement between the observed and the calculated damage.

  • Análisis comparativo del peligro sísmico de Barcelona

     Aguilar Meléndez, Armando; Pujades Beneit, Luis Gonzaga; Ordaz Schroeder, Mario Gustavo; Barbat Barbat, Horia Alejandro; Lantada Zarzosa, Nieves; García Elías, Alejandro; Campos, Amelia
    Congreso Nacional de Ingeniería Sísmica
    Presentation's date: 2013-11-07
    Presentation of work at congresses

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  • Enfoque integral para la evaluación de efectos de sitio en ciudades y su aplicación en Bogotá

     Bernal Granados, Gabriel Andres; Cardona, Omar Darío; Barbat Barbat, Horia Alejandro; Salgado, Mario
    Congreso Nacional de Ingeniería Sísmica, Colombia
    Presentation's date: 2013-05
    Presentation of work at congresses

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    A methodology for modeling site effects in cities is presented. This methodology is based on the definition of the prevailing geological formations and their relation to soft soil deposits within the urban area. Based on the geological interpretation for the city area, the elevation (over the sea level) of the geological contacts is defined, and a tridimensional geometrical model of geological formations is obtained. Available geotechnical data, gathered from an exhaustive geotechnical field research, is used to assign soil types and parameters to the previously defined geological formations. Static and dynamic soil characteristics are defined as random variables and their probability moments are computed form statistical estimations over the geotechnical data. A grid is defined over the city and for each grid node a synthetic soil deposit model is obtained with soil parameters assigned following their statistical distributions. Dynamic response is computed, for each grid node, by means of a 1D linear equivalent non-linear analysis, using a set of accelerograms which are compatible with the seismic hazard at bedrock level for the city. Spectral transfer functions of strong motion intensities are computed at each grid site. The application of this methodology in Bogotá is presented, and results are discussed in comparison with the current building construction requirements in the city.

  • Seismic response and torsional effects of RC structure with irregular plant and variations in diaphragms, designed with Venezuelan codes

     Herrera González, Reyes Indira; Vielma Pérez, Juan Carlos; Ugel Garrido, Ronald David; Barbat Barbat, Horia Alejandro; Pujades Beneit, Luis Gonzaga
    International Conference on Earthquake Resistant Engineering Structures
    Presentation's date: 2013-07
    Presentation of work at congresses

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    The objective of this study is to determine the seismic response and torsional effects of an existing Reinforced Concrete building with irregular plant and five levels projected according to an older version of Venezuelan seismic design code. Two structures were analysed: the original building and a redesigned version. Nonlinear static analysis and nonlinear 3D dynamic analysis were applied, based on registers of three synthetic accelerograms compatible with the elastic design spectrum for the used code. In 3D analysis, four structures were simulated, with and without rigid diaphragms so as to compare the seismic behaviour of the buildings. Through this nonlinear analysis parameters were determined that define the behaviour of the structure, torsional moments and rotations in columns reached for simulated buildings. Also, to obtain damage fragility curves for five states damage were generated. Results show that the original structure has an inadequate resistant behaviour and a high probability of exceeding the moderate damage state, while the redesigned structure presents good performance under seismic events according to the existing code. It was also observed that maximum torsional effects occur in the entrant corners of the irregular plant, which are reduced in mid-rise buildings by using a rigid diaphragm.

  • Hybrid loss exceedance curve (HLEC) for risk assessment

     Velázquez, César; Cardona, Omar Darío; Yamín, Luis E.; Mora Cuevas, Miguel; Carreño Tibaduiza, Martha Liliana; Barbat Barbat, Horia Alejandro
    International Symposium Computational Civil Engineering
    Presentation's date: 2013-05-24
    Presentation of work at congresses

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    Countries need to assess the expected risk due to natural hazards as a permanent activity in their financial plan; otherwise, they will experience a lack in the information required by the application of disaster risk reduction policies. In this article, a risk assessment methodology is proposed that uses, in one hand, empiric estimations of loss, based on information available in local disaster data bases, allowing to estimate losses due to small events; on the ot her hand, it uses probabilistic evaluations to estimate loss for greater or even catastrophic events for which information is not available due the lack of historical data. A ¿hybrid¿ loss exceedance curve, which represents the disaster risk in a proper and complete way, is thus determined. This curve merges two components: the corresponding to small and moderate losses, calculated by using an inductive and retrospective analysis, and the corresponding to extreme losses, calculated by using a deductive and prospective analysis. Applications of this new probabilistic risk assessment technique are given in this article for three countries.

  • Seismic and structural response of a framed four level building with RC and steel structure designed according to current Venezuelan codes

     Ugel Garrido, Ronald David; Herrera González, Reyes Indira; Vielma Pérez, Juan Carlos; Barbat Barbat, Horia Alejandro; Pujades Beneit, Luis Gonzaga
    International Conference on Earthquake Resistant Engineering Structures
    Presentation's date: 2013-07
    Presentation of work at congresses

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    This study determines the structural behavior of a four level framed building with composite RC and steel structure designed according Venezuelan seismic codes. The structural system consists of RC frames in the first three levels and steel frames in the fourth. It was performed linear analysis to design all structural elements. Capacity curves and performance points were obtained with pushover analysis. Results showed greater ductility in the X frames¿ direction and greater resistance reserve in the external frames. Performing points showed adequate resistance values but low stiffness in two Y frames¿ directions. Seismic action is carried on through synthetic accelerograms defined by the seismic codes used in this study. Dynamic analysis is used to compute parameters of ductility, over strength and displacements. In one case the collapse Limit State was reached, implying a general collapse of the building. Incremental dynamic analysis was performed to obtain fragility curves and damage probability matrix; a very high probability of significant lateral displacement and damage was evidenced from this despite a normative design of structural elements.

  • Seismic damage evaluation of an RC dissipative wall

     Baetu, Sergiu; Ciongradi, Ioan-Petru; Barbat Barbat, Horia Alejandro
    BULETINUL INSTITUTULUI POLITEHNIC DIN IASI - AUTOMATIC CONTROL and COMPUTER SCIENCE Section
    Date of publication: 2013-04
    Journal article

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    An economic design of buildings based on performance criteria takes into account the dissipation of the seismic energy accumulated in the structure. In a tall structural wall, plastic hinges appear only at the base of the wall and the rest of the wall, which has not ductility resources, remains undamaged. A solution to increase the seismic performance of a reinforced concrete structural wall is to create a slit zone with short connections. Yielding of this shear connections increases the energy dissipation. The objective of these solutions is to create an improved structure for tall multi-storey buildings that has a rigid behaviour at low seismic action and turns into a ductile one in the case of a high intensity earthquake. In this paper, a comparative nonlinear dynamic analysis between slit walls and solid walls is performed by means of SAP2000 software and using a layer model. Our main objective is to evaluate the damage of slit walls in comparison with that of a solid wall.

  • Un enfoque para evaluar la vulnerabilidad sísmica de edificios de concreto reforzado de baja altura

     Vielma Pérez, Juan Carlos; Herrera González, Reyes Indira; Ugel Garrido, Ronald David; Martínez, Yolsanie; Barbat Barbat, Horia Alejandro
    Ingenier¿a
    Date of publication: 2013-08
    Journal article

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    In this study is realized the seismic vulnerability assessment of an existing reinforced concrete building with two levels, through a deterministic approach using mechanical methods and non-linear analysis. A mathematical model of the existing building, Original Building, (EO) was developed. Then, it was developed the Resized Building (ER) model, which was designed considering the strong column-weak beam principle. Finally the model Displacement Method Building (EMD) was designed. These models were projected under two different methodologies, according to Venezuelan codes and considering a high seismic hazard. Through the non-linear static and dynamic analysis, it was obtained the seismic behavior of the three buildings. It was established the level of damage on the structures through the procedure of the objective damage index and were generated fragility curves and probability of damage matrices, indicating the Limit States reaching the buildings. The Original Building presented a non appropriate seismic behavior and a high probability of damage in the limit state of extensive damage. On the other hand, ER and EMD buildings presented a satisfactory earthquake resistant behavior and a high probability of light damage.

  • Análisis dinámico no lineal de edificio educacional con estructura de acero, Barquisimeto, Venezuela

     Ugel Garrido, Ronald David; Herrera González, Reyes Indira; Vielma Pérez, Juan Carlos; Barbat Barbat, Horia Alejandro
    Revista internacional de ingeniería de estructuras
    Date of publication: 2013
    Journal article

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  • Probabilistic earthquake risk assessment using CAPRA: application to the city of Barcelona, Spain

     Marulanda Fraume, Mabel Cristina; Carreño Tibaduiza, Martha Liliana; Cardona, Omar Darío; Ordaz Schroeder, Mario Gustavo; Barbat Barbat, Horia Alejandro
    Natural hazards
    Date of publication: 2013-10
    Journal article

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    The risk evaluation model CAPRA (Comprehensive Approach to Probabilistic Risk Assessment) is a techno-scientific methodology and information platform, composed of tools for evaluating and communicating risk at various territorial levels. The model allows evaluating losses on exposed elements using probabilistic metrics, such as the loss exceedance curve, the expected annual loss and the probable maximum loss, useful for multi-hazard risk analyses. In this article, the process of probabilistic seismic risk analysis is described, explaining the main features of the CAPRA modules of hazard, vulnerability and risk estimation applied to the city of Barcelona, Spain. In addition, according to the physical risk results and the information on the socioeconomic indicators of the city, this article presents the holistic evaluation of seismic risk, which is a valuable result to facilitate the integrated risk management by the different stakeholders involved in risk reduction decision making.

  • Capacity, fragility and damage in reinforced concrete buildings: a probabilistic approach

     Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Hurtado Gomez, Jorge Eduardo
    Bulletin of earthquake engineering
    Date of publication: 2013-12
    Journal article

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    The main goals of this article are to analyze the use of simplified deterministic nonlinear static procedures for assessing the seismic response of buildings and to evaluate the influence that the uncertainties in the mechanical properties of the materials and in the features of the seismic actions have in the uncertainties of the structural response. A reinforced concrete building is used as a guiding case study. In the calculation of the expected spectral displacement, deterministic nonlinear static methods are simple and straightforward. For not severe earthquakes these approaches lead to somewhat conservative but adequate results when compared to more sophisticated procedures involving nonlinear dynamic analyses. Concerning the probabilistic assessment, the strength properties of the materials, concrete and steel, and the seismic action are considered as random variables. The Monte Carlo method is then used to analyze the structural response of the building. The obtained results show that significant uncertainties are expected; uncertainties in the structural response increase with the severity of the seismic actions. The major influence in the randomness of the structural response comes from the randomness of the seismic action. A useful example for selected earthquake scenarios is used to illustrate the applicability of the probabilistic approach for assessing expected damage and risk. An important conclusion of this work is the need of broaching the fragility of the buildings and expected damage assessment issues from a probabilistic perspective.

  • Deterministic and probabilistic earthquake scenarios for the seismic risk analysis of URM buildings

     Avila Haro, Jorge Arturo; Gonzalez Drigo, Jose Ramon; Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro
    Key engineering materials
    Date of publication: 2013-05-02
    Journal article

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    Barcelona, as well as a large number of cities in the Mediterranean basin, has a housing stock composed of a large number of unreinforced brick masonry buildings. Motivated by different factors, the enlargement of the city (Eixample in Catalan) was held from the second half of the 19th century and the beginning of the 20th, a period in which a large number of buildings of this type were built, many of which are still used as dwellings. Although the buildings were built individually, some of them are linked to adjacent buildings by the side walls. This feature leads to the analysis of the buildings as isolated structures and also as an aggregate. Barcelona is located in a seismic region of low to moderate hazard, with macroseismic intensity between the grades VI and VII of the European macroseismic scale EMS'98. Based on the deterministic and probabilistic response spectra for the different types of soils present in Barcelona obtained in the work of Irizarry (2004), the seismic risk of four individual buildings and an aggregate is evaluated. The buildings are modeled and analyzed using the TREMURI program and MATLAB routines under the guidance of RISK-UE project.

  • Modelización numérica del comportamiento constitutivo del daño local y global y su correlación con la evolución de las frecuencias naturales en estructuras de hormigón reforzado  Open access

     Paredes Lopez, Jairo Andrés
    Defense's date: 2013-11-11
    Universitat Politècnica de Catalunya
    Theses

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    Esta tesis surge de la necesidad de establecer un método racional y práctico para identificar, a través del cambio de las frecuencias naturales , el daño en estructuras de hormigón armado. Por lo que se desarrolla un nuevo modelo constitutivo de daño diferenciado con dos variables internas de daño utilizando una única superficie de discontinuidad para tracción, compresión y cortante; asimismo, se plantea un procedimiento numérico para el cálculo de las frecuencias naturales con sus formas modales de vibración para diferentes estados de daño de estructuras de hormigón armado; se presenta una metodología para correlacionar daño global y frecuencias naturales . Esta tesis se desarrollará en el marco del análisis de estructuras y la mecánica computacional, particularmente, del análisis de materiales compuestos utilizando la teoría de mezclas serie/paralelo. Los resultados numéricos obtenidos se han comparado con resultados experimentales y numéricos obtenidos de la literatura, se ha observado buenos ajustes de los resultados

    This thesis emerges from the need to establish a rational and smart method to estimate the global damage through changes on eigenfrequency of concrete structures. Therefore, a new constitutive damage model is developed with two scalar inner variables and using only one surface of discontinuity to traction, compression and shear. Additionally, a numerical process has been proposed to calculate eigenfrequencies and eigenvectors of concrete structure with different levels of damage. A methodology to correlation ship between global damage and changes on e1genfrequencies has been proposed. This thesis is based on structural analysis and computational mechanics and, particularly, on analysis of composite materials using serial/parallel mix theory. The numerical results obtained in this thesis is have been compared with experimental and numerical results obtained of literature, and can be seen a good fit.

  • Análisis y gestión del riesgo sísmico de edificios y sistemas esenciales  Open access

     Valcarcel Torres, Jairo Andres
    Defense's date: 2013-02-01
    Department of Strength of Materials and Structural Engineering, Universitat Politècnica de Catalunya
    Theses

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    Los daños por terremotos en edificios y sistemas esenciales han motivado la definición de estándares de comportamiento de estas instalaciones, buscando reducir las pérdidas económicas y la pérdida de funcionalidad. Varias iniciativas nacionales y regionales han sugerido procedimientos para la evaluación del comportamiento y fragilidad de los edificios. Estos avances han dado soporte para la gestión de programas nacionales y regionales para la reducción de la vulnerabilidad de instalaciones esenciales, en los cuales se debe decidir entre ejecutar obras de reforzamiento o bien, renovar la infraestructura. En este trabajo se adoptan y presentan metodologías para evaluar la seguridad y riesgo sísmico, así como la factibilidad de las actividades de reducción de pérdidas, con el fin de priorizar el análisis detallado y orientar programas de reducción de la vulnerabilidad sísmica de edificios y sistemas esenciales. Estos procedimientos se aplican en diferentes casos de estudio, a escala local, regional, nacional y supranacional, realizando evaluaciones sobre centros educativos y centros de salud, entre otros edificios de importancia especial. Respecto a la evaluación de la seguridad sísmica de los edificios esenciales, se adopta un método simplificado basado en espectros de capacidad, propuesto en el proyecto RISK UE para evaluar su comportamiento y calificar su seguridad de acuerdo a los estándares sugeridos por el Comité VISION 2000. Para este análisis, los edificios se clasifican en tipologías estructurales para las cuales se conocen espectros de capacidad. Para estimar la acción sísmica (en roca firme), se adaptan espectros de amenaza uniforme a las formas espectrales del Eurocódigo 8. Para evaluar la acción sísmica en superficie, se emplean espectros de respuesta para diferentes tipos de suelo, de acuerdo a los resultados de estudios de mesozonación sísmica. A partir de la evaluación del comportamiento y daño esperado de los edificios, se presentan alternativas para evaluar las pérdidas económicas, índices de funcionalidad, así como estimaciones del tiempo de recuperación, que permiten identificar las instalaciones más críticas. Estos procedimientos se aplican a edificios esenciales de Cataluña (España), considerando periodos de retorno de 475 y 975 años. A escala local, esta metodología se aplica a los edificios esenciales ubicados en la Comarca de Val d’Arán. Este análisis permite evaluar su seguridad y priorizarlos según los daños esperados. De estos resultados se encuentra que cerca del 70% de los edificios son operacionales para periodos de retorno de 475 años. Para periodos de retorno de 975 años, son menos del 10% los edificios no cumplen con el nivel de comportamiento de seguridad de la vida. En cuanto a los daños esperados, el promedio de las instalaciones, para un periodo de retorno de 475 años, tienen un índice de pérdida económica del 25%. En cuanto a su funcionalidad, se observa que cerca del 50% tienen un índice de funcionalidad menor a 0.5. A escala regional, el mismo procedimiento se aplica para evaluar la seguridad de un conjunto de centros educativos de Cataluña, compuesto por instalaciones ubicadas en la Comarca de Val d’Aran, en la Provincia de Girona, así como edificios construidos con sistemas industrializados, la mayoría situados en la Provincia de Barcelona. Del total de centros analizados, para un periodo de retorno de 475 años, son menos del 5% las instalaciones que no cumplen con el nivel de comportamiento operacional. Para un periodo de retorno de 975 años, todos los centros educativos cumplen con el requisito de seguridad de la vida. El promedio de la pérdida económica de los centros de Girona se encuentra entre el 15% y el 20%. El promedio de la pérdida económica del conjunto de edificios industrializados es inferior al 5%. Para los centros educativos de de Val d’Aran, el promedio de la pérdida económica es del 25%. En forma similar, se desarrolla una evaluación de la seguridad de un conjunto de hospitales públicos de Cataluña. Para eventos de periodo de retorno de 475 años, cerca del 16% no cumplen el nivel de comportamiento operacional. Para eventos de periodo de retorno de 975 años, todos los hospitales cumplen con el requisito de seguridad de la vida. Además de la evaluación del comportamiento, se estiman índices de pérdida económica, de funcionalidad y se propone un Índice de Vulnerabilidad de Hospitales que incluye aspectos estructurales, no estructurales y de capacidad de respuesta a emergencias. Como complemento a la verificación de estándares de seguridad, en este trabajo se adoptan metodologías para la estimación de pérdidas esperadas ante un conjunto de eventos potencialmente dañinos, descritos por su magnitud y tasa de recurrencia. Dichos eventos se generan de acuerdo a la sismicidad de la zona de estudio. Para cada evento se evalúan las aceleraciones espectrales correspondientes al lugar donde se hallan las instalaciones empleando leyes de atenuación. Los edificios se clasifican en tipologías estructurales para las cuales se desarrollan curvas de vulnerabilidad. Dichas curvas relacionan la pérdida esperada y su desviación estándar con la aceleración espectral. Bajo este análisis es posible estimar la pérdida máxima probable para eventos de diferentes periodos de retorno, así como la pérdida anual esperada. Esta metodología se aplica a escala supranacional para evaluar relaciones de beneficio-costo de la reducción del riesgo sísmico en el área construida de centros educativos públicos de países de América Latina. Este análisis se centra en las pérdidas económicas y permite identificar los países en los cuales resulta viable la intervención estructural. Estos resultados se comparan con índices de progreso del sector educativo y de inversión pública en educación, con el fin de identificar los países en los cuales, los daños en la infraestructura escolar representan altos costos de oportunidad y pueden afectar el cumplimiento de los objetivos y metas en educación. Para la gestión de la seguridad de los edificios y sistemas esenciales, además de la estimación de las pérdidas económicas, es de interés evaluar las pérdidas asociadas a la interrupción del servicio durante terremotos, así como los impactos del desastre. Para el primer caso, se desarrolla un modelo para evaluar la respuesta de los hospitales durante eventos sísmicos. En este modelo se estiman el número de pacientes ingresados, en espera y no tratados oportunamente en un conjunto de hospitales. Este análisis se desarrolla para el conjunto de hospitales públicos de Cataluña para periodos de retorno de 475 y 975 años, así como para un conjunto de eventos generados de acuerdo a la peligrosidad sísmica de la región de estudio. De este análisis se encuentra que los hospitales con comportamiento crítico son aquellos ubicados en las zonas de mayor densidad de población y de mayor peligrosidad sísmica, en las cuales se espera que ocurran más heridos y que los hospitales puedan tener mayores daños. Para periodos de retorno de 475 años, el porcentaje de heridos no tratados oportunamente en el sistema puede llegar a ser del 8% y del 25% para periodos de retorno de 975 años. Para evaluar el impacto socioeconómico de los daños por terremotos en edificios esenciales, en este trabajo se adoptan metodologías para estimar los efectos sobre la población asociados a la reducción del funcionamiento de las instalaciones luego de eventos sísmicos. Estos procedimientos se aplican a un conjunto de hospitales públicos de Cataluña, con el fin de evaluar la reducción en la producción de salud, teniendo en cuenta diferentes escenarios de daños. La producción de salud se considera como el resultado de los servicios médicos ofrecidos con la infraestructura y recursos hospitalarios disponibles, los cuales influyen en la salud de la población. La producción de salud se mide en términos de la tasa de mortalidad (número de personas fallecidas anualmente por cada mil habitantes). De esta manera, una reducción en la producción de salud está relacionada con aumentos en la tasa de mortalidad. En el modelo adoptado, la producción de salud se relaciona con indicadores de los recursos sanitarios como el número de camas, personal médico y el diagnóstico de pacientes empleando nuevas tecnologías. De los resultados de este análisis se encuentra que, para escenarios de periodo de retorno de 475, la reducción en la producción de salud está relacionada con incrementos en la tasa de mortalidad de 0.84 muertos por cada mil habitantes. Dicho incremento es de de 1.14 para periodos de retorno de 975 años. Las metodologías propuestas y los resultados obtenidos son útiles para evaluar la importancia de la seguridad sísmica de los edificios y sistemas esenciales. Además de la verificación de los estándares de seguridad, los índices de pérdida económica, de funcionalidad, el análisis de respuesta ante emergencias y los impactos luego del desastre permiten identificar los beneficios de la reducción de la fragilidad de las instalaciones, dando soporte a programas de mitigación del riesgo.

    In this thesis, several methods to evaluate the seismic safety and seismic risk of essential and special buildings and systems are developed and applied. Those procedures are applied to case studies. Concerning the safety analysis, the seismic action is defined by means of response spectra which are defined according to the spectral shapes proposed In Euro-code EC 08. The soils effects are taken into account using the results of a seismic mesozonation study; buildings are defined by means of their bilinear capacity spectra but they are grouped ac-cording to simplified structural typologies. The expected damage is then estimated by means of a capacity spec-trum based method. Finally, the buildings safety is evaluated comparing the expected damage grades and the levels of seismic performance proposed by the Vision 2000 Committee. In the proposed method expected economic losses, residual functionality and recovery time periods also can be estimated. The obtained results allow identifying the buildings with worse seismic performance and can be useful for prioritizing vulnerability and risk reduction measures. The seismic safety study has been applied at local and regional scales. At local scale the buildings of special importance in the municipalities of Val d¿Aran (Spain) has been analyzed; at regional scale the methods are applied to a set of schools and public hospitals of Catalonia (Spain). Moreover well-known methods for seismic risk assessment were used to estimate expected losses in essential facilities when they are exposed to a set of potential harmful seismic events, which are defined by their magnitudes and recurrence rates. Then stochastic techniques are used to generate a family of such events according to the seismicity of the region of interest. For each event and for each building, the spectral accelerations at the site of the building are estimated by using seismological models linking magnitudes and spectral amplitudes and attenuation laws. Then, for each building typology, curves relating the expected economic losses and the spectral acceleration are developed. The method also allows estimating the corresponding standard deviations. The method can be applied before and after of hypothetical measures for reducing the vulnerability and seismic risk. Therefore, on this basis it is possible to estimate annual average losses according to the seismic hazard of the studied region. This procedure has been applied, at national and supranational scale, to obtain appraisals of the benefit-cost ratios of seismic risk reduction actions in schools in countries of Latin America. An added value of this thesis comes from the methods for assessing also the expected indirect losses associated to the disruption of essential and special facilities during earthquakes, as well as those related to the socioeconomic impacts of the disaster. In this context, a model was developed that allows evaluating the whole performance of a hospital network during seismic events. The method is based on the assessment, for each event, of the numbers of inpatients, injured people in waiting list and injured people not receiving treatment opportunely. The method also allows obtaining quantitative estimates of the expected reduction in the assistance of the health of the population. The methods and techniques proposed and used in this thesis, as well as the results obtained in specific case stud-ies, are useful for evaluating the actual seismic safety of essential facilities. Besides, the verification of the levels of performance, the assessment of indices of economic losses and of residual functionality, the analysis of the response, capacity and resilience to face emergencies and the detailed study of the impacts of the disasters, allow identifying the benefits of activities oriented to the reduction of the seismic vulnerability and risk, even in low to moderate seismic hazard areas.

  • Análisis estructural estático y dinámico probabilista de edificios de hormigón armado. Aspectos metodológicos y aplicaciones a la evaluación del daño.  Open access

     Vargas Alzate, Yeudy Felipe
    Defense's date: 2013-07-09
    Universitat Politècnica de Catalunya
    Theses

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    Esta tesis propone una metodología de evaluación del daño sísmico basada en el método del espectro de capacidad pero con un enfoque probabilista que se apoya en simulaciones Monte Carlo. Así la acción sísmica, la estructura y el daño esperado se consideran y se analizan como variables aleatorias. La metodología, que se valida mediante el análisis dinámico incremental, es una nueva, robusta y potente herramienta de análisis de riesgo tanto a nivel de edificios individuales como a nivel urbano y regional. La validación mediante el análisis dinámico, de hecho, ha supuesto crear también una metodología probabilista basada en el análisis dinámico incremental. El daño esperado puede obtenerse para cualquier intervalo de confianza permitiendo así, a los gestores de la protección civil la elección de los niveles prioritarios o de interés. Como el análisis dinámico incremental requiere acelerogramas, se ha optado por usar registros de terremotos y se ha diseñado una técnica que, para una determinada base de datos, permite optimizar, minimizando la dispersión, el número de acelerogramas compatibles con un determinado espectro de respuesta; de esta forma la incertidumbre en la acción sísmica se considera de una manera adecuada. Aunque a efectos metodológicos, se ha estimado suficiente y adecuado considerar como variables aleatorias gaussianas sólo las propiedades resistentes del hormigón y el acero, con todo se ha introducido también una nueva e interesante forma de incorporar la variabilidad espacial de la resistencia de vigas y columnas. Los desarrollos metodológicos se ilustran con numerosos casos de estudio de edificios existentes y bien documentados. En particular, se han estudiado los edificios de hormigón armado con forjados reticulares, clasificados en altos, de altura mediana y bajos. Este estudio se ha realizado considerando acciones sísmicas compatibles con los espectros previstos en el eurocódigo EC8 para terremotos tipo 1 y tipo 2 y para suelos A, B, C, D y E. La aplicación del método a edificios irregulares ha confirmado la insuficiencia de modelos 2D en estructuras asimétricas. Así, el método probabilista se ha aplicado a dos edificios de especial importancia para escenarios sísmicos de interés. El primero es el hospital de Vielha, para la acción sísmica con un periodo de retorno de 475 años; el segundo es un edificio del Barrio de San Fernando en Lorca, que fue severamente dañado por el terremoto del mes de mayo de 2011. En este segundo caso la acción sísmica se ha definido de forma determinista mediante las dos componentes horizontales de aceleración registradas en la ciudad. En los análisis 3D se ha incorporado el efecto de direccionalidad, concluyendo que edificios del mismo tipo situados en un mismo lugar pueden sufrir daños significativamente distintos dependiendo sólo de su orientación azimutal. Los resultados obtenidos en el caso de Lorca son compatibles con los daños observados lo que contribuye a validar el método probabilista y los desarrollos implementados en esta tesis.

    This dissertation proposes a methodology for seismic damage assessment based on the capacity spectrum method but with a probabilistic approach which is supported on Monte Carlo simulation. The seismic action, the structure and the expected damage are considered and analyzed as random variables. The method, which is validated through incremental dynamic analysis, is a new, robust and powerful tool for risk analysis that can be applied to individual buildings, but also at urban and regional scales. In fact, the validation through dynamic analyses has involved creating also a probabilistic method for damage assessment, based on incremental dynamic analysis. The expected damage can be obtained for any confidence interval thus allowing the civil protection managers choosing the levels of priority or interest. As incremental dynamic analyses require accelerograms, the use of earthquake records has been preferred and it has been developed a specific technique that, for a given database, minimizes the dispersion and optimizes the number of accelerograms compatible with a given response spectrum; in this way, the uncertainties in the seismic action are considered in an appropriate manner. Although for methodological purposes it was estimated sufficient and adequate to consider only the strength properties of concrete and steel as Gaussian random variables, yet a new and interesting way to incorporate the spatial variability of the strength of beams and columns has been also proposed. The methodological developments are illustrated with numerous case studies of existing and well documented buildings. Specifically, reinforced concrete buildings with waffle slabs, classified as low-rise, mid-rise and high-rise, have been studied. This study has been conducted considering seismic actions compatible with the response spectra foreseen in the Eurocode EC8 for type 1 and type 2 earthquakes and soil classes A, B, C, D and E. The application of the method to irregular buildings confirmed the insufficiency of 2D models for asymmetric structures. Thus, the probabilistic method has been applied to two buildings of special importance for seismic scenarios of interest. The first one is the hospital of Vielha considering the seismic action with a return period of 475 years; the second one is a building located in the neighborhood of San Fernando in Lorca, which was severely damaged by the earthquake of May 2011. In this second case the seismic action has been defined deterministically by means of the two horizontal accelerograms recorded in the city. In 3D analyses the directionality effect is considered, concluding that buildings of the same type located in the same place can suffer significantly different damages depending only of their azimuthal angle. The results obtained in the case of Lorca are compatible with the observed damage. This fact supports the validity of the probabilistic method as well as that of the developments implemented in this thesis.

  • Modelación probabilista de pérdidas ecconómicas por sismo para la estimación de la vulnerabilidad fiscal del estado y la gestión financiera del riesgo soberano  Open access

     Marulanda Fraume, Mabel Cristina
    Defense's date: 2013-04-25
    Universitat Politècnica de Catalunya
    Theses

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    El riesgo sísmico y en general los desastres futuros que puede sufrir una ciudad, una región o un país significan una obligación o pasivo contingente no explícito que puede afectar, desde el punto de vista macroeconómico, la sostenibilidad fiscal del Estado. En otras palabras, del riesgo de desastre se deriva una exposición fiscal que debe ser dimensionada de acuerdo con la responsabilidad del Estado, el cual es un tomador de riesgo, consciente o no, que debe formular una estrategia para afrontar dicho riesgo y, así, evitar efectos económicos adversos que afecten su sostenibilidad económica. En esta investigación se ilustra el porqué tanto los desastres extremos como los desastres menores recurrentes significan una exposición fiscal y son pasivos contingentes que deben tenerse en cuenta en el balance contable de las naciones. La evaluación de la vulnerabilidad fiscal frente a desastres depende del potencial de pérdidas económicas que puede llegar a tener un país y de la capacidad o resiliencia económica que tiene para afrontarlas y llevar a cabo la reposición o reconstrucción postdesastre. Aquí se sustenta que la forma más apropiada para llevar a cabo dicha evaluación es utilizando modelos probabilistas de riesgo que den cuenta del potencial de pérdidas máximas esperadas para un período de retorno y de modelos analíticos que permitan determinar la capacidad o el acceso a recursos económicos que permitan cubrir el déficit que puede generar un desastre. El presente documento presenta el tipo de técnicas actuariales con las cuales se puede dimensionar la exposición fiscal, evaluando en forma probabilista el daño estructural y las pérdidas que se derivan sobre los activos o bienes inmuebles de responsabilidad del Estado. La modelización probabilista del riesgo catastrófico y el inventario de efectos económicos de los eventos menores recurrentes son insumos fundamentales para proyectar mecanismos financieros factibles y estructuras alternativas de retención y transferencia del riesgo de acuerdo con análisis de optimización financiera. Dicha modelización actuarial permite proponer índices para asignar la prioridad de rehabilitación o refuerzo estructural de inmuebles utilizando la relación beneficio-costo de este tipo de intervenciones. Se presenta una descripción de los instrumentos financieros que se podrían explorar para definir una estrategia óptima de protección financiera. Se describe la aplicación de la modelización probabilista del riesgo sísmico a nivel urbano para el caso de Manizales, Colombia, con el propósito de ilustrar el diseño del seguro colectivo voluntario por terremoto para las edificaciones privadas, que actualmente está operando, cubriendo a los estratos sociales de bajos ingresos de la ciudad a través de un subsidio cruzado. También se presenta el cálculo del riesgo sísmico y las estrategias financieras de gestión del riesgo para Bogotá, Colombia, y la evaluación del riesgo sísmico de Barcelona, España, utilizando métricas probabilistas. Finalmente se incluye el análisis de riesgo sísmico del portafolio de edificaciones públicas de Colombia, para ilustrar un análisis de riesgo a nivel de un país y los resultados de riesgo, utilizando indicadores, para los países de las Américas y a nivel mundial, con el fin de dar cuenta del riesgo nacional (i.e. para el sector público y privado) y el riesgo soberano (i.e. de responsabilidad fiscal) de los países del mundo.

    Seismic risk and in general the potential disasters that a city, a region or a country can suffer mean a non-explicit contingent liability that can affect, from a macroeconomic perspective, the fiscal sustainability of the State. In other words, disaster risk derives in a fiscal exposure that has to be measure according to the responsibility of the State, which is a risk taker, conscious or not, that must develop a strategy to face that risk, thus, to avoid adverse economic effects that affect its economic sustainability. This research illustrates why both, extreme disasters and recurrent small disasters meand a fiscal exposure and why they are contingen liabilities that must be considered in the national balance of the countries. Fiscal vulnerability evaluation due to disasters depends on the potential economic losses that a country could have, and the ability or economic resilience that it has, to face them and carry out a post disaster recovery and reconstruction. It is explained the most appropriate way to develop an evaluation using probabilistic risk models that provides the potential maximum expected losses for a specific return period and describes how analytical models allow determining the ability to access economic resources to cover deficit that a disaster could generate. This document presents the kinds of actuarial techniques useful to measure fiscal exposure or fiscal vulnerability, evaluation, in a probabilistic way, structural damage and losses produced over the assets that are a fiscal responsibility of the government. Probabilistic catastrophe risk modeling and inventory of economic impact of recurrent small events are fundament supplies to propose feasible financial mechanisms and alternative structures of risk retention and risk transfer according to financial optimization analysis. This actuarial modeling allows proposing indices to prioritize, using cost/benefit rates, rehabilitation or structural reinforcement of assets. This thesis also presents a description of the financial instruments that can be explored to define an optimal strategy of financial protection. The document also presents the application of probabilistic seismic risk moddeling at urban level in three cities: The case of Manizales, Colombia illustrates the desighno of the voluntary collective earhtquake insurance of private buildings, which currentlycovers low-income homeowners of the city through a cross subsidy strategy; the seismic risk estimation and financial risk strategies for Bogota, Colombia; and the sismic risk evaluation of Barcelona, Spain. Finally, this thesis illustrates risk analysis at country level through presenting seismic risk analysis of public buildings portfolio of Colombia. Also, it describes a risk analysis at regional level in the Americas and at global level, using indicators to represent national risk (of public and private sectors) and sovereign risk (fiscal responsibility) of the whole countries of the world.

  • Seismic performance of unreinforced masonry buildings: application to Barcelona, Spain

     Avila Haro, Jorge Arturo; Gonzalez Drigo, Jose Ramon; Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Cattari, Serena
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09-24
    Presentation of work at congresses

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  • Probabilistic assessment of the seismic risk of Barcelona

     Aguilar Meléndez, Armando; García-Elías, A.; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Lantada Zarzosa, Nieves; Ordaz Schroeder, Mario Gustavo
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09
    Presentation of work at congresses

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  • Probabilistic vulnerability assessment of a reinforced concrete structure by using a 3-D model

     Vargas Alzate, Yeudy Felipe; Barbat Barbat, Horia Alejandro; Pujades Beneit, Luis Gonzaga; Hurtado, J.E.
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09
    Presentation of work at congresses

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  • Probabilistic assessment of the seismic damage in reinforced concrete buildings

     Barbat Barbat, Horia Alejandro; Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Hurtado Gomez, Jorge Eduardo
    International Symposium Computational Civil Engineering
    Presentation's date: 2012-05-25
    Presentation of work at congresses

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    The main objective of this article is to assess the expected seismic damage in reinforced concrete buildings from a probabilistic point of view by using Monte Carlo simulation. To do that, the seismic behavior of the building is studied by using random capacity obtained by considering the mechanical properties of the materials as random variables. Starting from the capacity curves, one can obtain the damage states and the fragility curves as well as to develop curves describing the expected seismic damage of the structures as a function of a seismic hazard characteristic. The latter can be calculated using the capacity spectrum and the demand spectrum according to the methodology proposed by the RISK-UE project. For defining the seismic demand as a random variable, a set of real accelerograms are obtained from the European and Spanish databases in such a way that the mean of their elastic response spectra is similar to an elastic response spectrum selected from Eurocode 8. In order to combine the uncertainties associated with the seismic action and the mechanical properties of materials, two procedures are considered for obtaining functions which relates the PGA to the maximum spectral displacements. The first one is based on a series of nonlinear dynamic analyses. The second one is based on the well known procedure named equal displacement approximation exposed in ATC 40. After applying both procedures, the probability density functions of the maximum displacement at the roof of the building are obtained and compared. The expected structural damage is finally obtained by replacing the spectral displacement obtained by using the ATC 40 and the incremental dynamic procedure. In the damage functions the results obtained from incremental static and dynamic analyses are finally compared and discussed from a probabilistic point of view.

  • Deterministic and probabilistic earthquake scenarios for the seismic risk analysis of URM buildings

     Avila Haro, Jorge Arturo; Gonzalez Drigo, Jose Ramon; Vargas Alzate, Yeudy Felipe; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro
    International Conference on Fracture and Damage Mechanics
    Presentation's date: 2012-09-19
    Presentation of work at congresses

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  • Smart scaling of accelerograms applied to the study of steel buildings

     Bermúdez, C.A.; Hurtado, J.E.; Barbat Barbat, Horia Alejandro; Pujades Beneit, Luis Gonzaga
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09
    Presentation of work at congresses

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  • Seismic risk scenarios in a cross-border zone of the Pyrenees

     Monfort, D.; Negulescu, Caterina; Roullé, Agathe; Colas, B.; Lantada Zarzosa, Nieves; Valcarcel Torres, Jairo Andres; Rodríguez, J.; Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Irizarry, Janira; Susagna Vidal, Teresa; Macau, Albert; Figueras Vila, Sara; Goula Suriñach, Xavier
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09
    Presentation of work at congresses

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  • Earthquake vulnerability assessment of buildings for catastrophic risk analysis in urban areas

     Yamín, Luis E.; Hurtado, A. I.; Barbat Barbat, Horia Alejandro; Bernal Granados, Gabriel Andres; Cardona, Omar Darío
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09-27
    Presentation of work at congresses

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    A catastrophic risk model has been developed to evaluate, building by building, the probabilistic losses and pure premiums of different portfolios. The model includes a hazard module, an exposure module, a vulnerability module and a risk module. A brief summary of the methodological approach adopted for catastrophic risk assessment and an improvement methodological approach for the vulnerability assessment of building structures is presented. Dynamic nonlinear or simplified nonlinear analysis, the consideration of multiple damage functions for different types of components of the construction and a repair cost methodological approach are proposed in order to integrate the total economic losses for the building, for different performance levels of analysis. The methodology is illustrated with a one-story, one-bay reinforced concrete moment resisting frame with unreinforced masonry infill walls. Preliminary conclusions and recommendations are presented for the implementation of the proposed methodology.

  • The Quadrants Method: a procedure to evaluate the seismic performance of existing buildings

     Vielma Pérez, Juan Carlos; Martínez, Y; Barbat Barbat, Horia Alejandro; Oller Martinez, Sergio Horacio
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09-25
    Presentation of work at congresses

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    In this work a new simple procedure for the evaluation of the seismic performance is formulated. It combines the results of non-linear static analysis with a specific Limit State defined by inter-storey drift-based damage threshold and the seismic demand obtained from the inelastic design spectrum. With both values it is possible to define four zones in the capacity curve which characterizes four different seismic performances. The procedure is used to evaluate two reinforced concrete framed buildings, the first one consist in a typical lowrise building designed according to current Venezuelan codes; the second one is a four-storey building designed according to older code, whose had been damaged by fire. Results shown both cases do not meet the Quadrants Method criterion then they need to be redesigned. Redesigned buildings were submitted to a non-linear dynamic analysis, representative of three hazard levels associated with three Limit States. These redesigned buildings met all the objectives associated with the hazard levels, showing the efficiency of the method for the rapid evaluation of the seismic performance of existing buildings.

  • CAPRA - Comprehensive Approach to Probabilistic Risk Assessment: international initiative for risk management effectiveness

     Cardona, Omar Darío; Ordaz Schroeder, Mario Gustavo; Reinoso, Eduardo; Yamín, Luis; Barbat Barbat, Horia Alejandro
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09-26
    Presentation of work at congresses

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    Understanding disaster risk due to hazard events, such as earthquakes, creates powerful incentives for countries to develop planning options and tools to reduce potential damages. This has been the reason why CAPRA, the risk evaluation model described in this paper, was developed with the technical and financial support of the World Bank, the Inter-American Development Bank (IDB) and the International Strategy of United Nations for Disaster Reduction (ISDR). CAPRA is a techno-scientific methodology and information platform, composed of tools for the evaluation and communication of risk at various territorial levels. This model allows the evaluation of probabilistic losses on exposed elements using probabilistic metrics, such as the exceedance probability curve, expected annual loss and probable maximum loss, useful for multi-hazard/risk analyses. The platform is conceptually oriented to facilitate decision making. Using CAPRA it is possible to design risk transfer instruments, the evaluation of probabilistic cost-benefit ratio, providing an innovative tool for decision makers to analyze the net benefits of the risk mitigation strategies, such as building retrofitting. This model is useful for land use planning, loss scenarios for emergency response, early warning, on-line loss assessment mechanisms, and for the holistic evaluation of disaster risk based on indicators that facilitates the integrated risk management by the different stakeholders involved in risk reduction decision-making. CAPRA has been used in Central and South America and in some countries of Europe and Asia. It has been the base for the evaluation of the country´s risk profile for Colombia, Mexico and Nepal in the framework of the United Nations Global Assessment Report GAR-2011 and it is a potential contribution for the Global Earthquake Model (GEM).

  • Probabilistic seismic risk assessment of Barcelona, Spain

     Cardona, Omar Darío; Marulanda Fraume, Mabel Cristina; Carreño Tibaduiza, Martha Liliana; Barbat Barbat, Horia Alejandro
    International Symposium Computational Civil Engineering
    Presentation's date: 2012-05-25
    Presentation of work at congresses

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    Understanding disaster risk due to hazard events, such as earthquakes, creates powerful incentives for countries to develop planning options and tools to reduce potential damages. The results of the seismic risk assessment of the city of Barcelona using CAPRA (Comprehensive Approach for Probabilistic Risk Assessment) presented in this paper involve the evaluation of probabilistic losses of the exposed elements using probabilistic metrics, such as the exceedance probability curve, the expected annual loss and the probable maximum loss, which are useful for multi-hazard/risk analyses. The outcomes obtained with technoscientific methodologies like CAPRA are oriented to facilitate decision-making. Using CAPRA, it is possible to design risk transfer instruments; evaluation of probabilistic cost-benefit ratio, to consider the net benefits of risk mitigation strategies; land use planning, loss scenarios for emergency response, early warning, on-line loss assessment mechanisms and holistic evaluation of disaster risk based on indicators. These applications facilitate the integrated risk management by the different stakeholders involved in risk reduction decisionmaking.

  • Holistic evaluation of the seismic risk in Barcelona by using indicators

     Carreño Tibaduiza, Martha Liliana; Cardona, Omar Darío; Barbat Barbat, Horia Alejandro
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09-26
    Presentation of work at congresses

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    This article presents a methodology which evaluates the seismic risk from a holistic perspective, that is, 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. Indicators are used in order to capture favourable conditions for direct physical impacts, as well as indirect and, at times, intangible impacts of hazard events. In the case of Barcelona, the seismic hazard has been simulated by using the CRISIS 2007 code. The vulnerability of the buildings in the city of Barcelona has been defined with vulnerability functions using the Vulnerability Module of the CAPRA platform. These functions are defined for each building typology; the used typologies were defined in ICC/CIMNE (2004). This case study is part of the results obtained in the MOVE project of the European Commission.

  • Design and implementation of a collective insurance program based on cross subsidies for recovery of low income homeowners

     Marulanda Fraume, Mabel Cristina; Barbat Barbat, Horia Alejandro; Cardona, Omar Darío; Mora Cuevas, Miguel
    World Conference on Earthquake Engineering
    Presentation's date: 2012-09-25
    Presentation of work at congresses

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    Understanding disaster risk due to hazard events creates powerful incentives to develop planning options and tools to reduce and finance potential damages. This paper describes how probabilistic metrics such as the loss exceedance curve, the expected annual loss and the probable maximum loss, calculated with catastrophe risk models, are used for the designing of a risk transfer instrument to cover the private housing in Manizales, Colombia. This voluntary collective instrument promotes the insurance culture and provides financial protection not only to the estate-tax payers but also covers the low-income homeowners through a cross-subsidy strategy. This program is promoted by the city administration and the insurance industry, using the mechanism of the property-tax payment. This collective insurance helps the government to access key resources for low-income householder recovery and improve disaster risk management at local level.

  • New methodology for urban seismic risk assessment from a holistic perspective

     Carreño Tibaduiza, Martha Liliana; Cardona, Omar. D.; Barbat Barbat, Horia Alejandro
    Bulletin of earthquake engineering
    Date of publication: 2012-04
    Journal article

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  • Estudio numérico-experimental de la interfaz hormigón-epoxi-FRP para una estructura reforzada sometida a doble corte

     Molina, Maritzabel; Cruz Solis, Juan Jose; Oller Martinez, Sergio Horacio; Barbat Barbat, Horia Alejandro; Gil Espert, Lluis
    Revista internacional de métodos numéricos para cálculo y diseño en ingeniería
    Date of publication: 2012-02
    Journal article

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  • Numerical-experimental study of the FRP-epoxy-concrete interface for reinforced structures under double shear

     Molina Herrera, Maritzabel; Cruz Solis, Juan Jose; Oller Martinez, Sergio Horacio; Barbat Barbat, Horia Alejandro; Gil Espert, Lluis
    Revista internacional de métodos numéricos para cálculo y diseño en ingeniería
    Date of publication: 2012
    Journal article

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  • Seismic response of high-rise steel framed buildings with Chevron-braced designed according to Venezuelan codes

     Ugel Garrido, Ronald David; Vielma Pérez, Juan Carlos; Herrera González, Reyes Indira; Pérez, Sigrit; Barbat Barbat, Horia Alejandro
    Natural Science
    Date of publication: 2012-08
    Journal article

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    The object of this study is to determine the seismic response of regular high-rise steel buildings with chevron-braced frames. Mechanics models of three buildings of 14, 18 and 20 stories are studied, all of them with similar geometric characteristics in plant and elevation. These models are realized using prescriptions and parameters from venezuelan design codes. The seismic action is carry on through varius synthetic design spectrum compatible accelerograms defined by the seismic codes in this study, with three levels of intensity corresponding to three specific Limit States. Dynamic analysis is used to compute parameters of ductility, over strength and maximum displacements. From these results it can be concluded that chevron-braced frames presented a good overall performance and non V-braced frames show greater damage due to dynamic actions, validating non linear dynamic analysis as a very powerful tool to seismic-resistance design and chevron-braced frames as a very useful choice in improving the response of tall steel structures. since this lateral bracing system is absent from Venezuelan seismic codes.

  • Dimensionado sísmico de edificios porticados de hormigón armado mediante factores de amplificación con base en energía

     Vielma Pérez, Juan Carlos; Barbat Barbat, Horia Alejandro; Oller Martinez, Sergio Horacio
    Hormigon y acero
    Date of publication: 2012
    Journal article

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    El proyecto sismorresistente de estructuras actual se realiza mediante una serie de prescripciones normativas que persiguen garantizar su adecuado comportamiento. Los procedimientos actuales de análisis se realizan utilizando el comportamiento elástico, aplicando los factores de reducción de respuesta para obtener fuerzas sísmicas equivalentes, representativas del comportamiento inelástico que pueden alcanzar las estructuras al ser sometidas a la acción de sismos fuertes. A partir de los resultados del análisis elástico se obtienen los desplazamientos inelásticos, amplificados mediante factores que son función de los factores de reducción; sin embargo, se ha observado una amplia variación en los valores de los factores de amplificación prescritos en las normas a nivel mundial, por lo que se justifica profundizar en el estudio de dichos factores. En este trabajo se presenta un procedimiento de dimensionado sísmico con base en la respuesta no lineal. El procedimiento es aplicado a un conjunto de edificios regulares de hormigón armado de diferentes alturas, proyectados para niveles altos de amenaza sísmica y es evaluado aplicando análisis dinámico no lineal para tres Estados Límite, correlacionado con tres umbrales de daño que se definen a través de las derivas de planta. Los resultados demuestran que el procedimiento es adecuado para realizar el dimensionado sísmico de edificios, proporcionando al proyectista criterios de evaluación más cónsonos con las características de los edificios y de la amenaza sísmica.

  • Probabilistic assessment of seismic risk of Barcelona, Spain, using the CAPRA platform

     Marulanda Fraume, Mabel Cristina; Carreño Tibaduiza, Martha Liliana; Cardona, Omar Darío; Barbat Barbat, Horia Alejandro
    BULETINUL INSTITUTULUI POLITEHNIC DIN IASI - AUTOMATIC CONTROL and COMPUTER SCIENCE Section
    Date of publication: 2012-03
    Journal article

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    The Comprehensive Approach for Probabilistic Risk Assessment (CAPRA), is a robust methodology for modeling risk which allows identifying the most important aspects of catastrophes. CAPRA performs the evaluation of losses of the exposed elements using probabilistic metrics, such as the loss exceedance curve, the expected annual loss and the probable maximum loss, which are useful for multi-hazard risk analysis. The outcomes obtained with such a technical-scientific methodology are oriented to facilitate decision-making. They allow designing risk transfer instruments, evaluating the cost¿benefit ratio, developing risk mitigation strategies and loss scenarios for emergency response, etc. The CAPRA platform is described in this paper by using as a testbed the city of Barcelona, Spain. Nevertheless, the results included for this urban area have not only a high scientific interest but also a practical one, because they are useful in taking risk reduction decision by the Municipality.

  • Optimal design and earthquake-resistant design evaluation of low-rise framed RC structure

     Herrera González, Reyes Indira; Vielma Pérez, Juan Carlos; Ugel Garrido, Ronald David; Martínez, Yolsanie; Barbat Barbat, Horia Alejandro
    Natural Science
    Date of publication: 2012-08
    Journal article

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    This study evaluates the seismic response of an existing two stories RC building using non-lin-ear analysis. The original model was resized and two buildings were designed using two different methodologies to fulfill the Venezuelan codes requirements for a high seismic hazard. An elas- tic analysis was applied to the original building in order to verify interstory drifts; the resizing building was designed under requirements of strong column-wake beam condition. A third building was modeled according to the seismic displacement-based design procedure. A non- linear static analysis and 2D and 3D dynamic analyses were performed, obtaining capacity curves, structural ductility, structural perform-ance point, global and interstory drifts for each building. Torsional effects for the resizing build- ing were also computed from 3D analysis. In the original building a weak seismic behavior was obtained, while resized buildings presented a good seismic performance under the Limits States evaluated in this study.

  • Access to the full text
    Comportamiento sismico de los edificios de Lorca  Open access

     Carreño Tibaduiza, Martha Liliana; Lantada Zarzosa, Nieves; Irizarry, Janira; Valcarcel Torres, Jairo Andrés; Barbat Barbat, Horia Alejandro; Goula Suriñach, Xavier
    Física de la Tierra
    Date of publication: 2012
    Journal article

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    Después de ocurrido el terremoto de Lorca, el 11 de mayo de 2011, el Institut Geològic de Catalunya (IGC), la Universidad Politécnica de Cataluña (UPC) y la Asociación Española de Ingeniería Sísmica (AEIS) organizaron, junto con las asociaciones de ingeniería sísmica francesa (AFPS) y portuguesa (SPES), una visita técnica con el objeto de realizar observaciones que permitieran calibrar, verificar y validar los métodos utilizados en las evaluaciones de riesgo sísmico en zonas urbanas. Este artículo resume los aspectos más destacados en cuanto a la observación de la vulnerabilidad de edificios de vivienda, así como de edificios de especial importancia como son hospitales y escuelas. After the earthquake of Lorca, May 11, 2011, the Geological Institute of Catalonia (IGC), the Technical University of Catalonia (UPC) and the Spanish Association for Earthquake Engineering (AEIS) organized a technical visit in order to compile information that allow to calibrate, to verify and to validate the methods used in seismic risk assessments in urban areas. This article summarizes the highlights regarding the vulnerability of residential buildings and buildings of special importance such as hospitals and schools.

  • Efectos de los esfuerzos cortantes biaxiales en la respuesta sísmica de columnas de hormigón armado  Open access

     Osorio Bustamante, Edison
    Defense's date: 2012-12-14
    Department of Construction Engineering, Universitat Politècnica de Catalunya
    Theses

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    Durante un terremoto, las columnas de hormigón armado pueden verse sometidas a movimientos bidireccionales que pueden afectar su capacidad resistente y ductilidad. Sin embargo, las normas de diseño y evaluación sísmica no aportan recomendaciones explícitas para cuantificar el comportamiento de las columnas bajo dichas cargas. Esta investigación busca contribuir al análisis y cuantificación de los efectos de los esfuerzos cortantes biaxiales en la respuesta sísmica de columnas de hormigón armado. Con este objetivo, se realizó una recopilación del estado del conocimiento orientado a la revisión de los estudios experimentales y las estrategias de modelización numérica disponibles. De los estudios experimentales se concluyó que las columnas bajo cargas laterales bidireccionales ven reducida su capacidad resistente y ductilidad en comparación a las cargadas en una dirección. La deformación lateral del hormigón bajo cargas de compresión se ha estudiado pero no se encontró un modelo de su comportamiento bajo cargas cíclicas. En esta investigación, se estudió el comportamiento de la deformación lateral del hormigón mediante la ejecución de una primera campaña experimental en probetas cilíndricas de hormigón con cargas de compresión uniaxial cíclica. Con este estudio se aportaron curvas experimentales de tensión - deformación longitudinal y lateral con carga monótona y cíclica en hormigones de resistencia normal y alta. A partir de la interpretación de los datos experimentales, se propuso un modelo conceptual del comportamiento de la deformación lateral del hormigón. De forma paralela, se revisó y estudió el comportamiento de la deformación lateral del hormigón en un estado en compresión triaxial con base en resultados experimentales publicados en la literatura. Con las conclusiones de este estudio y el modelo conceptual en compresión uniaxial, se formuló un modelo analítico de la dilatancia del hormigón en compresión cíclica que se implementó en una ecuación constitutiva 3D. Los resultados se verificaron con los datos experimentales del hormigón en diferentes estados de compresión triaxial y diferentes materiales de confinamiento. Con la finalidad de alcanzar el objetivo general de la investigación, se diseñó, implementó y ejecutó una segunda campaña experimental en columnas con cargas unidireccionales y bidireccionales. Diez columnas circulares de hormigón armado se diseñaron y fabricaron con una disposición de armadura transversal insuficiente para que presentaran un nivel de ductilidad baja a media y un fallo por un mecanismo de cortante-flexión. Cuatro de estas columnas, fueron encamisadas con polímeros reforzados con fibras; dos con fibra de carbono (CFRP) y dos con fibra de aramida (AFRP). En los ensayos bajo carga bidireccional, la demanda de deformación en la armadura transversal fue mayor respecto al de carga unidireccional debido a que las deformaciones por esfuerzos cortantes y por la acción de confinamiento se acumulan. Las columnas con menor cuantía de armadura transversal y menor cuantía de FRP presentaron un incremento de la longitud de la rótula plástica. Dentro de esta investigación, se realizaron análisis de las columnas ensayadas con modelo seccional TINSA(Total-Interaction-Nonlinear-Section). El modelo seccional representa el decremento de resistencia y ductilidad y la mayor deformación de los cercos que se presentó en los experimentos con cargas bidireccionales. Por último, los efectos de los esfuerzos cortantes se analizaron a nivel material, seccional y de elemento. Se derivaron expresiones analíticas para considerar los efectos de los esfuerzos cortantes en el diagrama tensión-deformación del hormigón, la relación momento - curvatura y la longitud de la rótula plástica. Las expresiones analíticas encontradas se usaron en un modelo de análisis de rótula concentrada para obtener la curva de capacidad de la columna. Los resultados del modelo se corroboraron con los resultados experimentales de esta investigación.

    During an earthquake, reinforced concrete columns may be subjected to bi-directional displacements undermining their strength and ductility. However, the current codes for the seismic design and assessments of structures do not provide explicit provisions for the quantification of the effects of biaxial shear forces on the seismic response of reinforced concrete columns. This investigation is aimed at contributions to the analysis and quantification of the effects of biaxial shear forces on the seismic response of reinforced concrete columns. With this purpose, a state of the art review about the available experimental studies and numerical modeling strategies was performed. From the experimental studies, it is concluded that both the strength and ductility of the columns subjected to biaxial shear forces are reduced with respect to those subjected to uniaxial shear forces. The lateral deformation of concrete under compressive loads has been studied but has not formulated a model of its behavior under cyclic loading. In this research, a first experimental program on cylindrical concrete specimens subjected to cyclic compression was carried out in order to study the lateral deformation behavior. Experimental longitudinal stress- longitudinal and lateral strain curves, under monotonic and cyclic loading were provided, for normal and high strength concrete specimens. A conceptual model of the lateral behavior of concrete was proposed since interpretation of experimental data. Subsequently, the lateral behavior of concrete under a triaxial compression stress was reviewed and studied based on the experimental results available in the literature. Based on conclusions findings and using the conceptual model for uniaxial compression, an analytical model for the dilatancy of concrete under cyclic compression was formulated, which incorporate the above mentioned phenomena. The model was implemented into a 3D constitutive equation and their results were verified with experimental results under different triaxial stress states and different confinement materials. With the purpose of reaching the general objective of the investigation, a second experimental program on columns subjected to uniaxial and biaxial lateral forces and axial load was performed. Ten reinforced concrete circulars columns were designed and built, with an inadequate transverse reinforcement arrangement, providing insufficient ductility level so that a shear-flexure failure mechanism would take place. With the purpose of studying the behavior of strengthened columns under biaxial loading, four specimens were wrapped with carbon fiber reinforced polymers (FRP): two with carbon fiber (CFRP) and two with aramid fiber (AFRP). Under cyclic biaxial shear loading, the demand of strains in the transverse reinforcement was bigger than uniaxial loading because the strain by shear and the action of confinement were accumulated. The columns with smaller transverse reinforcement ratios and smaller FRP ratios showed increase of plastic hinge length. In this investigation, sectional analyses of the experimental behavior of the columns tested were performed with TINSA (Total-Interaction-Nonlinear-Section). The sectional model reproduces the decrement of strength and ductility as well as the greater strain in the hoops that was experimentally observed under biaxial tests. Finally, the effect of shear forces was analyzed at the material, section and structure levels. Analytical expressions were derived to consider the influence of the shear forces on the concrete stress-strain relationships, moment-curvature diagrams and on the plastic hinge length. The obtained analytical expressions were used in an analysis model of concentrated plastic hinges in order to obtain the capacity curve of the column. The model results were validated by comparing them satisfactorily with the experimental results presented in this investigation.

  • Simulación de los materiales compuestos como refuerzo en estructuras de hormigón armado

     Molina Herrera, Maritzabel
    Defense's date: 2012-01-12
    Department of Strength of Materials and Structural Engineering, Universitat Politècnica de Catalunya
    Theses

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  • MAGNETORHEOLOGICAL DAMPERS: MODELING AND CONTROL DESIGN FOR CIVIL ENGINEERING STRUCTURES

     Aguirre Carvajal, Naile
    Defense's date: 2012-02-03
    Department of Geotechnical Engineering and Geo-Sciences, Universitat Politècnica de Catalunya
    Theses

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  • Seismic performance of a block of buildings representative of the typical construction in the Eixample district in Barcelona (Spain)

     Pujades Beneit, Luis Gonzaga; Barbat Barbat, Horia Alejandro; Gonzalez Drigo, Jose Ramon; Avila Haro, Jorge Arturo; Lagomarsino, S.
    Bulletin of earthquake engineering
    Date of publication: 2012-02
    Journal article

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