http://hdl.handle.net/2117/3705 Sun, 19 May 2013 11:26:39 GMT 2013-05-19T11:26:39Z webmaster.bupc@upc.edu Universitat Politècnica de Catalunya. Servei de Biblioteques i Documentació no http://hdl.handle.net/2117/19178 Title: Proyecto y construccion del cierre del ábside de la Sagrada Familia Authors: Buxadé, Carles; Gómez Serrano, José; Espel, Ramon; Grima, Rosa; Buxadé, Agata; Ferrando, Ramon; Aguado de Cea, Antonio Mon, 13 May 2013 11:08:52 GMT http://hdl.handle.net/2117/19178 2013-05-13T11:08:52Z Buxadé, Carles; Gómez Serrano, José; Espel, Ramon; Grima, Rosa; Buxadé, Agata; Ferrando, Ramon; Aguado de Cea, Antonio no Sagrada Familia, Gaudí, construcción, ábside, estructura y materiales http://hdl.handle.net/2117/19006 Title: New analytical model to generalize the Barcelona Test using axial displacement Authors: Pujadas Álvarez, Pablo; Blanco Álvarez, Ana; Pialarissi Cavalaro, Sergio Henr; Fuente Antequera, Albert de la; Aguado de Cea, Antonio Abstract: The Barcelona Test has proved to be very suitable for the systematic control of the tensile properties of Fibre Reinforced Concrete (FRC). Nevertheless, the need to measure the total circumferential opening displacement (TCOD) of the specimen entails the use of an expensive circumferential extensometer. In order to simplify the test, studies from the literature propose the use of the axial displacement of the press (δ) instead of the TCOD, obtaining empirical equations to correlate the energy estimated with both measurements. However, these equations are only valid for δ ranging from 1 to 4 mm and were adjusted based on the test results of just a few types of FRC. The verification of this formulation for other types of FRC shows an average error of 51.1%, thus limiting the simplification proposed for the test. In this paper, a new analytical model to convert the δ into the TCOD is developed and validated for a wide range of FRC. Besides being applicable to the whole range of δ, the new model provides a clear physical understanding of the main mechanism observed during the test and shows an average error of only 6.7%, making it possible to simplify the Barcelona test. Fri, 26 Apr 2013 11:30:56 GMT http://hdl.handle.net/2117/19006 2013-04-26T11:30:56Z Pujadas Álvarez, Pablo; Blanco Álvarez, Ana; Pialarissi Cavalaro, Sergio Henr; Fuente Antequera, Albert de la; Aguado de Cea, Antonio no The Barcelona Test has proved to be very suitable for the systematic control of the tensile properties of Fibre Reinforced Concrete (FRC). Nevertheless, the need to measure the total circumferential opening displacement (TCOD) of the specimen entails the use of an expensive circumferential extensometer. In order to simplify the test, studies from the literature propose the use of the axial displacement of the press (δ) instead of the TCOD, obtaining empirical equations to correlate the energy estimated with both measurements. However, these equations are only valid for δ ranging from 1 to 4 mm and were adjusted based on the test results of just a few types of FRC. The verification of this formulation for other types of FRC shows an average error of 51.1%, thus limiting the simplification proposed for the test. In this paper, a new analytical model to convert the δ into the TCOD is developed and validated for a wide range of FRC. Besides being applicable to the whole range of δ, the new model provides a clear physical understanding of the main mechanism observed during the test and shows an average error of only 6.7%, making it possible to simplify the Barcelona test. http://hdl.handle.net/2117/18749 Title: Design of macro-synthetic fibre reinforced concrete pipes Authors: Fuente Antequera, Albert de la; Campos Escariz, Renata; Domingues de Figueiredo, Antonio; Aguado de Cea, Antonio Abstract: This paper presents an experimental campaign in which concrete pipes were manufactured using plastic fibres as the sole reinforcement material. In this regard, it has been demonstrated that the use of plastic fibres is compatible with pipe production systems, and that, when subjected to the crushing test (CT), plastic fibre reinforced pipes yield strength classes that are attractive in terms of the growth of this material in the concrete pipe industry. Moreover, the results obtained from both the characterisation of the material and the mechanical behaviour of the pipes have been used to verify that the Model for the Analysis of Pipes (MAPs) is an appropriate tool for the design of such pipes. Finally, this paper presents a direct design methodology which was used to establish the firsts design tables for fibre reinforced concrete pipes presented in the scientific literature. This methodology can be used to estimate the strength requirements of the fibre reinforced concrete needed to reach the strength classes set out in EN 1916:2002, without having to resort to the CT as an indirect design method. Tue, 09 Apr 2013 18:29:17 GMT http://hdl.handle.net/2117/18749 2013-04-09T18:29:17Z Fuente Antequera, Albert de la; Campos Escariz, Renata; Domingues de Figueiredo, Antonio; Aguado de Cea, Antonio no This paper presents an experimental campaign in which concrete pipes were manufactured using plastic fibres as the sole reinforcement material. In this regard, it has been demonstrated that the use of plastic fibres is compatible with pipe production systems, and that, when subjected to the crushing test (CT), plastic fibre reinforced pipes yield strength classes that are attractive in terms of the growth of this material in the concrete pipe industry. Moreover, the results obtained from both the characterisation of the material and the mechanical behaviour of the pipes have been used to verify that the Model for the Analysis of Pipes (MAPs) is an appropriate tool for the design of such pipes. Finally, this paper presents a direct design methodology which was used to establish the firsts design tables for fibre reinforced concrete pipes presented in the scientific literature. This methodology can be used to estimate the strength requirements of the fibre reinforced concrete needed to reach the strength classes set out in EN 1916:2002, without having to resort to the CT as an indirect design method. http://hdl.handle.net/2117/18626 Title: Longitudinal time-dependent response of segmental tunnel linings Authors: Arnau Delgado, Oriol; Molins i Borrell, Climent; Blom, C.B.M.; Walraven, Joost Abstract: The longitudinal forces introduced by tunnel boring machines (TBMs) to the segmental tunnel linings influence their structural response. The analyses of the linings construction process and the ground-structure interaction mechanisms have shown the influence of the lining creep on the progressive loss of the initial longitudinal force. An analytical formulation to predict the remaining compression of the linings as a function of time is proposed, supported by means of a complete numerical model, which considers the effect of creep during the sequential construction process. An experimental program to determine the creep of plastic packers was developed, revealing its significant influence on the global lining creep factor and the evolution of the remaining compressive stresses. Thu, 04 Apr 2013 18:56:25 GMT http://hdl.handle.net/2117/18626 2013-04-04T18:56:25Z Arnau Delgado, Oriol; Molins i Borrell, Climent; Blom, C.B.M.; Walraven, Joost no Lining creep, Longitudinal response, Packers, Segmental tunnel lining The longitudinal forces introduced by tunnel boring machines (TBMs) to the segmental tunnel linings influence their structural response. The analyses of the linings construction process and the ground-structure interaction mechanisms have shown the influence of the lining creep on the progressive loss of the initial longitudinal force. An analytical formulation to predict the remaining compression of the linings as a function of time is proposed, supported by means of a complete numerical model, which considers the effect of creep during the sequential construction process. An experimental program to determine the creep of plastic packers was developed, revealing its significant influence on the global lining creep factor and the evolution of the remaining compressive stresses. http://hdl.handle.net/2117/18625 Title: Three dimensional structural response of segmental tunnel linings Authors: Arnau Delgado, Oriol; Molins i Borrell, Climent Abstract: The particular configuration of segmental tunnel linings produces that its structural response in front of usual design loads could present a significant three dimensionality due to the structural interaction between adjacent rings (coupling effects). The present paper studies the phenomena associated to coupling effects, determines the main involved parameters and analyzes their influence on a real lining structural response by means of a 3D numerical model. The comparison with the usual plane models currently employed in linings designs provide significant conclusions about the coupling effects implications and the conditions in which become more relevant. Thu, 04 Apr 2013 18:50:42 GMT http://hdl.handle.net/2117/18625 2013-04-04T18:50:42Z Arnau Delgado, Oriol; Molins i Borrell, Climent no Segmental tunnel linings, Coupling effects, 3D response, Numerical simulation, Nonlinear analysis The particular configuration of segmental tunnel linings produces that its structural response in front of usual design loads could present a significant three dimensionality due to the structural interaction between adjacent rings (coupling effects). The present paper studies the phenomena associated to coupling effects, determines the main involved parameters and analyzes their influence on a real lining structural response by means of a 3D numerical model. The comparison with the usual plane models currently employed in linings designs provide significant conclusions about the coupling effects implications and the conditions in which become more relevant. http://hdl.handle.net/2117/18538 Title: Tapered plate girders under shear : tests and numerical research Authors: Bedynek, Agnieszka; Real Saladrigas, Esther; Mirambell Arrizabalaga, Enrique Abstract: This paper presents an experimental and numerical research on tapered steel plate girders subjected to shear. Experimental tests included four small-scale tapered steel plate girders. Research was focused on both, critical shear load and ultimate shear resistance. Moreover, the post-buckling behaviour of tapered plates was studied. Further, some parametric studies with various geometries of tapered panels were done in order to find the most favourable design situations. The analysed parameters were: the panel aspect ratio, the inclined flange angle, the web and the flange slenderness. Numerical simulations allowed distinguishing four different typologies of tapered plate girders which should be considered separately in design because of their different behaviour. Verification of the simplified procedure for tapered plates proposed in Eurocode EN 1993-1-5 allowed concluding that for some cases the estimation of the ultimate shear resistance is situated on the unsafe side and need to be revised. Tue, 02 Apr 2013 11:10:38 GMT http://hdl.handle.net/2117/18538 2013-04-02T11:10:38Z Bedynek, Agnieszka; Real Saladrigas, Esther; Mirambell Arrizabalaga, Enrique no Tapered plate girders, Critical load, Shear resistance, Instability, FE model, Imperfections, Residual stress, Resal effect This paper presents an experimental and numerical research on tapered steel plate girders subjected to shear. Experimental tests included four small-scale tapered steel plate girders. Research was focused on both, critical shear load and ultimate shear resistance. Moreover, the post-buckling behaviour of tapered plates was studied. Further, some parametric studies with various geometries of tapered panels were done in order to find the most favourable design situations. The analysed parameters were: the panel aspect ratio, the inclined flange angle, the web and the flange slenderness. Numerical simulations allowed distinguishing four different typologies of tapered plate girders which should be considered separately in design because of their different behaviour. Verification of the simplified procedure for tapered plates proposed in Eurocode EN 1993-1-5 allowed concluding that for some cases the estimation of the ultimate shear resistance is situated on the unsafe side and need to be revised. http://hdl.handle.net/2117/18076 Title: An orthotropic damage model for the analysis of masonry structures Authors: Pelà, Luca; Cervera Ruiz, Miguel; Roca Fabregat, Pedro Abstract: This paper presents a numerical model for nonlinear analysis of masonry structural elements based on Continuum Damage Mechanics. The material is described at the macro-level, i.e. it is modeled as a homogeneous orthotropic continuum. The orthotropic behavior is simulated by means of an original methodology, resulting from the concept of mapped tensors from the anisotropic field to an auxiliary workspace. The application of this idea to strain-based Continuum Damage Models is innovative and leads to several computational benefits. The suitability of the model for representing the behavior of different types of brickwork masonry is shown via the simulation of experimental tests. Tue, 05 Mar 2013 17:20:17 GMT http://hdl.handle.net/2117/18076 2013-03-05T17:20:17Z Pelà, Luca; Cervera Ruiz, Miguel; Roca Fabregat, Pedro no Continuum damage mechanics, Orthotropy, Mapping, Transformation tensor, Masonry, FE analysis, Tensile cracking This paper presents a numerical model for nonlinear analysis of masonry structural elements based on Continuum Damage Mechanics. The material is described at the macro-level, i.e. it is modeled as a homogeneous orthotropic continuum. The orthotropic behavior is simulated by means of an original methodology, resulting from the concept of mapped tensors from the anisotropic field to an auxiliary workspace. The application of this idea to strain-based Continuum Damage Models is innovative and leads to several computational benefits. The suitability of the model for representing the behavior of different types of brickwork masonry is shown via the simulation of experimental tests. http://hdl.handle.net/2117/17670 Title: Generación automática de esquemas de bielas y tirantes considerando criterios constructivos Authors: Bairán García, Jesús Miguel Abstract: El método de bielas y tirantes (BT) es de gran utilidad en el dimensionamiento a rotura de elementos de hormigón, particularmente en casos de regiones D donde las hipótesis clásicas de vigas y placas no son aplicables. Aunque el método viene recogido en muchas normativas modernas, existen al menos tres aspectos que limitan un uso más extendido en la práctica: no da información en servicio, la selección de esquemas factibles no es trivial en casos complejos y la solución no es única. En este artículo se propone un método que genera esquemas factibles de BT mediante el uso de análisis lineales y criterios de optimización para modificar la distribución de propiedades del material en la región de estudio. No es necesario disponer un armado inicial y permite considerar criterios constructivos; en particular, se aborda el de armado ortogonal. Se incluyen casos de estudio y ofrecen conclusiones y perspectivas futuras. Strut-and-Tie (ST) method is very useful in the Ultimate Limit State design of reinforced concrete elements, particularly in the case of D regions where beam and plate theories cannot be applied. In spite of being included in most modern design codes, there are at least three issues that limit a more extended use of this method in practice: it doesn’t provide information in service, the selection of suitable schemes is not trivial for complex cases and the solution isn’t unique. In this paper a novel method to produce suitable ST schemes is proposed by combining linear elastic analyses and optimization criteria. It is based on suitable modifications of the distribution of elastic parameters in the structural model. Without requiring initial distribution of reinforcement, it is capable of considering constructability conditions, particularly the condition of orthogonal reinforcement layout is considered in this paper. A series of case-studies are presented and analyzed; finally, conclusions are drawn. Tue, 12 Feb 2013 15:51:56 GMT http://hdl.handle.net/2117/17670 2013-02-12T15:51:56Z Bairán García, Jesús Miguel no regiones D, método de bielas y tirantes, criterios constructivos, optimización topológica, campos de tensiones, D-regions, strut-and-tie method, constructability, topological optimization, stress fields El método de bielas y tirantes (BT) es de gran utilidad en el dimensionamiento a rotura de elementos de hormigón, particularmente en casos de regiones D donde las hipótesis clásicas de vigas y placas no son aplicables. Aunque el método viene recogido en muchas normativas modernas, existen al menos tres aspectos que limitan un uso más extendido en la práctica: no da información en servicio, la selección de esquemas factibles no es trivial en casos complejos y la solución no es única. En este artículo se propone un método que genera esquemas factibles de BT mediante el uso de análisis lineales y criterios de optimización para modificar la distribución de propiedades del material en la región de estudio. No es necesario disponer un armado inicial y permite considerar criterios constructivos; en particular, se aborda el de armado ortogonal. Se incluyen casos de estudio y ofrecen conclusiones y perspectivas futuras. Strut-and-Tie (ST) method is very useful in the Ultimate Limit State design of reinforced concrete elements, particularly in the case of D regions where beam and plate theories cannot be applied. In spite of being included in most modern design codes, there are at least three issues that limit a more extended use of this method in practice: it doesn’t provide information in service, the selection of suitable schemes is not trivial for complex cases and the solution isn’t unique. In this paper a novel method to produce suitable ST schemes is proposed by combining linear elastic analyses and optimization criteria. It is based on suitable modifications of the distribution of elastic parameters in the structural model. Without requiring initial distribution of reinforcement, it is capable of considering constructability conditions, particularly the condition of orthogonal reinforcement layout is considered in this paper. A series of case-studies are presented and analyzed; finally, conclusions are drawn. http://hdl.handle.net/2117/17222 Title: Lateral behavior of concrete under uniaxial compressive cyclic loading Authors: Osorio Bustamante, Edison; Bairán García, Jesús Miguel; Marí Bernat, Antonio Ricardo Abstract: In reinforced concrete structures under seismic loading, concrete is subjected to compressive cyclic stress. Although cyclic stress–strain response has been described before, the cyclic behavior of strains in the direction orthogonal to loading has not been characterized yet. Such behavior can be of great importance for evaluating the efficiency of the confinement under cyclic loading. For this purpose an experimental program on cylindrical specimens of concrete strength from 35 to 80 MPa subjected to uniaxial cyclic compression was carried out. Stress versus longitudinal and lateral strains curves have been obtained both for the hardening and softening branches under monotonic and cyclic loading. Governing parameters of the lateral behavior are identified and correlated to describe the response of the lateral strain. Additionally, an analytical model to obtain the lateral deformations of concrete under cyclic uniaxial compression has been formulated and verified experimentally. Finally, some examples are presented in order to illustrate the applicability of the proposed model and its possible incorporation into a 3D constitutive cyclic model. Wed, 09 Jan 2013 09:08:26 GMT http://hdl.handle.net/2117/17222 2013-01-09T09:08:26Z Osorio Bustamante, Edison; Bairán García, Jesús Miguel; Marí Bernat, Antonio Ricardo no In reinforced concrete structures under seismic loading, concrete is subjected to compressive cyclic stress. Although cyclic stress–strain response has been described before, the cyclic behavior of strains in the direction orthogonal to loading has not been characterized yet. Such behavior can be of great importance for evaluating the efficiency of the confinement under cyclic loading. For this purpose an experimental program on cylindrical specimens of concrete strength from 35 to 80 MPa subjected to uniaxial cyclic compression was carried out. Stress versus longitudinal and lateral strains curves have been obtained both for the hardening and softening branches under monotonic and cyclic loading. Governing parameters of the lateral behavior are identified and correlated to describe the response of the lateral strain. Additionally, an analytical model to obtain the lateral deformations of concrete under cyclic uniaxial compression has been formulated and verified experimentally. Finally, some examples are presented in order to illustrate the applicability of the proposed model and its possible incorporation into a 3D constitutive cyclic model. http://hdl.handle.net/2117/17076 Title: Viscoelasticity and damage model for creep behaviour of historical masonry structures Authors: Roca Fabregat, Pedro; Cervera Ruiz, Miguel; Pelà, Luca; Clemente, Roberto; Chiumenti, Michèle Abstract: This paper presents a continuum model for the simulation of the viscous effects and the long-term damage ac-cumulation in masonry structures. The rheological model is based on a generalized Maxwell chain representation with a constitutive law utilizing a limited number of internal variables. Thanks to its computational efficiency, this approach is suitable for the analysis of large and complex structures. In the paper, the viscous and damage models are presented and their coupling is discussed. The FE simulation of the construction process of the representative bay of Mallorca Cathedral is presented, together with the analysis of the long-term effects. The parameters of the model are tentatively calibrated on the basis of the time-dependent viscous deformations detected during the cathedral monitoring. Tue, 04 Dec 2012 14:28:33 GMT http://hdl.handle.net/2117/17076 2012-12-04T14:28:33Z Roca Fabregat, Pedro; Cervera Ruiz, Miguel; Pelà, Luca; Clemente, Roberto; Chiumenti, Michèle no This paper presents a continuum model for the simulation of the viscous effects and the long-term damage ac-cumulation in masonry structures. The rheological model is based on a generalized Maxwell chain representation with a constitutive law utilizing a limited number of internal variables. Thanks to its computational efficiency, this approach is suitable for the analysis of large and complex structures. In the paper, the viscous and damage models are presented and their coupling is discussed. The FE simulation of the construction process of the representative bay of Mallorca Cathedral is presented, together with the analysis of the long-term effects. The parameters of the model are tentatively calibrated on the basis of the time-dependent viscous deformations detected during the cathedral monitoring. http://hdl.handle.net/2117/16703 Title: Inductive method for assessing the amount and orientation of steel fibers in concrete Authors: Torrents Dolz, Josep M.; Blanco Álvarez, Ana; Pujadas Álvarez, Pablo; Aguado de Cea, Antonio; Juan Garcia, Pablo; Sánchez-Moragues, Miguel Ángel Abstract: Steel fibers are ferromagnetic and they have the property of altering the magnetic field around them. This paper discusses a method and gives a practical example to measure, non-destructively, the amount and orientation of fibers from cubic concrete specimens (150 mm). This is possible because the fibers affect inductance of a sensor (an inductive coil) that is wrapped around the specimen. Wed, 10 Oct 2012 11:41:57 GMT http://hdl.handle.net/2117/16703 2012-10-10T11:41:57Z Torrents Dolz, Josep M.; Blanco Álvarez, Ana; Pujadas Álvarez, Pablo; Aguado de Cea, Antonio; Juan Garcia, Pablo; Sánchez-Moragues, Miguel Ángel no Steel fibers are ferromagnetic and they have the property of altering the magnetic field around them. This paper discusses a method and gives a practical example to measure, non-destructively, the amount and orientation of fibers from cubic concrete specimens (150 mm). This is possible because the fibers affect inductance of a sensor (an inductive coil) that is wrapped around the specimen. http://hdl.handle.net/2117/16672 Title: Continuum FE models for the analysis of Mallorca Cathedral Authors: Roca Fabregat, Pedro; Cervera Ruiz, Miguel; Pelà, Luca; Clemente, Roberto; Chiumenti, Michèle Abstract: From the theoretical point of view, systems composed by masonry arches or vaults would require, during construction, the simultaneous activation of all structural elements in order to reach the optimum balance of thrusts. This is not obviously the case of complex ancient masonry constructions, whose long and gradual building process may have contributed to their deformed condition and even to damage. In this paper, the possible influence of the construction process as well as that of later long-term deformation on the final condition of the building is investigated in the case of a complex and large historical structure, namely Mallorca Cathedral. A FE code has been specifically developed for the present study. The code is able to account for construction processes through sequential-evolutionary analyses, with the description of masonry mechanical damage and long-term deformation. The representative bay of the cathedral is analyzed taking into account different construction phases, as emerged from historical research. The response of such substructure to transverse earthquake equivalent forces is then investigated. In this case, the damage model is improved with a local crack-tracking algorithm. This numerical strategy models the tensile damage as distinct cracks, leading to a better prediction of realistic collapsing mechanisms. Mon, 08 Oct 2012 12:30:49 GMT http://hdl.handle.net/2117/16672 2012-10-08T12:30:49Z Roca Fabregat, Pedro; Cervera Ruiz, Miguel; Pelà, Luca; Clemente, Roberto; Chiumenti, Michèle no Crack-tracking, Viscosity, Geometric nonlinearity, Localized damage, Historical construction, Gothic structure, Masonry, Construction process, Long-term effects, Continuum Damage Mechanics From the theoretical point of view, systems composed by masonry arches or vaults would require, during construction, the simultaneous activation of all structural elements in order to reach the optimum balance of thrusts. This is not obviously the case of complex ancient masonry constructions, whose long and gradual building process may have contributed to their deformed condition and even to damage. In this paper, the possible influence of the construction process as well as that of later long-term deformation on the final condition of the building is investigated in the case of a complex and large historical structure, namely Mallorca Cathedral. A FE code has been specifically developed for the present study. The code is able to account for construction processes through sequential-evolutionary analyses, with the description of masonry mechanical damage and long-term deformation. The representative bay of the cathedral is analyzed taking into account different construction phases, as emerged from historical research. The response of such substructure to transverse earthquake equivalent forces is then investigated. In this case, the damage model is improved with a local crack-tracking algorithm. This numerical strategy models the tensile damage as distinct cracks, leading to a better prediction of realistic collapsing mechanisms. http://hdl.handle.net/2117/16597 Title: Comparison of seismic assessment procedures for masonry arch bridges Authors: Pelà, Luca; Aprile, Alessandra; Benedetti, Andrea Abstract: This work delves into the seismic assessment of masonry bridges through a detailed analysis of an existing triple-arched bridge. Firstly, the effectiveness of the nonlinear static analysis is evaluated by means of a comparison with a comprehensive set of 84 nonlinear dynamic analyses. Secondly, the choice of the control node on the finite element structural model is investigated, in order to understand its influence on the prediction of seismic capacity. Although the node located at the top level is usually considered to characterize the force–displacement response of common structures, such a choice is not suitable for the considered case-study. The node located at the level of the bridge’s centre of mass proves to be a better choice since it ensures a more reliable estimation of the seismic capacity. The critical discussion of the numerical analyses results gives useful indications towards an improved procedure for the seismic assessment of the considered structural typology. Mon, 01 Oct 2012 16:33:41 GMT http://hdl.handle.net/2117/16597 2012-10-01T16:33:41Z Pelà, Luca; Aprile, Alessandra; Benedetti, Andrea no Masonry, Arch bridge, Pushover analysis, Nonlinear dynamic analysis, Control node, Earthquake response This work delves into the seismic assessment of masonry bridges through a detailed analysis of an existing triple-arched bridge. Firstly, the effectiveness of the nonlinear static analysis is evaluated by means of a comparison with a comprehensive set of 84 nonlinear dynamic analyses. Secondly, the choice of the control node on the finite element structural model is investigated, in order to understand its influence on the prediction of seismic capacity. Although the node located at the top level is usually considered to characterize the force–displacement response of common structures, such a choice is not suitable for the considered case-study. The node located at the level of the bridge’s centre of mass proves to be a better choice since it ensures a more reliable estimation of the seismic capacity. The critical discussion of the numerical analyses results gives useful indications towards an improved procedure for the seismic assessment of the considered structural typology. http://hdl.handle.net/2117/16379 Title: Efecto del enrollado y enderezado en las propiedades mecánicas de barras de acero de diámetro medio y grande fabricadas en rollo Authors: Bairán García, Jesús Miguel; Marí Bernat, Antonio Ricardo; Ortega, H.; Rosa, Juan Carlos Abstract: Las armaduras en rollo ofrecen grandes ventajas logísticas y medioambientales, por lo que tienden a fabricarse en diámetros medios y grandes. La fabricación introduce complejas historias de carga y temperatura produciendo tensiones residuales. En este artículo se presenta un estudio experimental y numérico sobre la incidencia en las propiedades mecánicas de las barras en rollo, principalmente en la ductilidad. La experimentación incluye fases de caracterización de las zonas del núcleo y corona de la barra, y la comparación entre barras rectas y barras enrolladas idénticas enderezadas en condiciones de laboratorio. El estudio numérico se basa en un modelo constitutivo de endurecimiento mixto y permite considerar la geometría real de la barra y las altas temperaturas involucradas. Se identifican los orígenes y distribuciones de las tensiones residuales y los principales efectos que se producen en las propiedades mecánicas. Finalmente, se recomiendan radios de rollos para controlar la pérdida de ductilidad. Tue, 31 Jul 2012 10:07:56 GMT http://hdl.handle.net/2117/16379 2012-07-31T10:07:56Z Bairán García, Jesús Miguel; Marí Bernat, Antonio Ricardo; Ortega, H.; Rosa, Juan Carlos no residual stresses, mixed-hardening, Armaduras en rollo, ductilidad, tensiones residuales, endurecimiento mixto, Coiled rebars, ductility Las armaduras en rollo ofrecen grandes ventajas logísticas y medioambientales, por lo que tienden a fabricarse en diámetros medios y grandes. La fabricación introduce complejas historias de carga y temperatura produciendo tensiones residuales. En este artículo se presenta un estudio experimental y numérico sobre la incidencia en las propiedades mecánicas de las barras en rollo, principalmente en la ductilidad. La experimentación incluye fases de caracterización de las zonas del núcleo y corona de la barra, y la comparación entre barras rectas y barras enrolladas idénticas enderezadas en condiciones de laboratorio. El estudio numérico se basa en un modelo constitutivo de endurecimiento mixto y permite considerar la geometría real de la barra y las altas temperaturas involucradas. Se identifican los orígenes y distribuciones de las tensiones residuales y los principales efectos que se producen en las propiedades mecánicas. Finalmente, se recomiendan radios de rollos para controlar la pérdida de ductilidad. http://hdl.handle.net/2117/16078 Title: Seismic damage assessment of waffled slabs RC buildings of Barcelona Authors: Moreno González, Rosángel; Bairán García, Jesús Miguel Abstract: The seismic damage of waffled-slabs reinforced concrete buildings in the city of Barcelona (Spain) is evaluated using Risk-UE methodology, which enables obtaining fragility curves of the structure in a simplified manner through capacity curves. The seismic hazard is described by means of the reduced 5%-damped elastic response spectrum specific to Barcelona. Capacity curves are obtained using a non-linear static analysis and are used to obtain the performance point and probability damage matrices corresponding to the specified seismic hazard. Four different buildings, representing most typical structure configuration used in the city, are studied based on detailed data from real structures. Despite low-to-moderate seismic hazard in the region, the results show that these buildings present a considerable seismic vulnerability and a relevant expected seismic damage due to its poor expected performance. Mon, 18 Jun 2012 14:19:44 GMT http://hdl.handle.net/2117/16078 2012-06-18T14:19:44Z Moreno González, Rosángel; Bairán García, Jesús Miguel no The seismic damage of waffled-slabs reinforced concrete buildings in the city of Barcelona (Spain) is evaluated using Risk-UE methodology, which enables obtaining fragility curves of the structure in a simplified manner through capacity curves. The seismic hazard is described by means of the reduced 5%-damped elastic response spectrum specific to Barcelona. Capacity curves are obtained using a non-linear static analysis and are used to obtain the performance point and probability damage matrices corresponding to the specified seismic hazard. Four different buildings, representing most typical structure configuration used in the city, are studied based on detailed data from real structures. Despite low-to-moderate seismic hazard in the region, the results show that these buildings present a considerable seismic vulnerability and a relevant expected seismic damage due to its poor expected performance.