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  • Investigation of the masonry pillars of a modernist building of Hospital de Sant Pau, Barcelona

     Drougkas, Anastasios; Roca Fabregat, Pedro; Molins Borrell, Climent; Alegre Heitzmann, Vicente
    International Conference on Structural Analysis of Historical Construction
    p. 1-8
    Presentation's date: 2014-10
    Presentation of work at congresses

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    The methodology employed and the results obtained from an experimental campaign to determine the compressive strength of a masonry pillar extracted from an early 20th century building are presented. The samples of the pillar were extracted from a structure located in the Hospital de Sant Pau modernist complex. The pillars analyzed are characterized by a circular section of a diameter of 60 cm, and are composed of clay bricks and, instead of the more common lime based mortars, Portland cement as a binder. The pillars show a complex interior morphology including an outer layer of regular masonry in combination with an internal core composed of an irregular mix of mortar and brick portions. The material, geometrical and structural typology of the pillars investigated are fairly representative of the pillars encountered throughout the hospital complex, therefore making the determination of its capacity of wide interest for the structural study of several adjacent buildings. The experimental campaign was planned and performed with the purpose of determining the compressive strength and elastic properties the masonry pillar under cyclic and monotonic concentric loading. The campaign included several tests on entire portions of the pillar measuring a height of 100 cm. It also included a detailed characterization of the mechanical properties of the constituent materials and masonry samples including one or more mortar joints. The ultimate load obtained from the pillar test is compared to the service and design loads. Comparisons are also drawn between the compressive strength obtained from the pillar test and from tests performed on sampled masonry specimens. The effects of existing damage, which is extensive in the pillars, and overall structural arrangement are also discussed.

  • Design optimization for a truncated catenary mooring system for scale model tests

     Molins Borrell, Climent; Trubat Casal, Pau; Gironella i Cobos, Framcesc Xavier; Campos Hortigüela, Alexis
    Offshore Renewable Energy, International Conference
    Presentation's date: 2014-09-17
    Presentation of work at congresses

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    One of the main aspects when testing floating offshore platforms is the scaled mooring system, particularly with the increased depths where such platforms are intended. When the existing testing facilities do not have enough available space, the use of truncated mooring systems with a similar behaviour to the real mooring system could be an interesting option. As part of the development of SPAR platform made of concrete for FOWTs a station keeping system with catenary shaped lines was selected. The test facility available for the planned experiments presented an important width constraint. Then, an algorithm to optimize the design of the scaled truncated mooring system by using different weights of lines was developed. The optimization process adjusts the quasi-static behaviour of the scaled mooring system as much as possible to the real mooring system within its expected maximum displacement range, where the catenary line provides the restoring forces by its suspended line length.

  • Numerical micro-modeling simulation of masonry in compression

     Drougkas, Anastasios; Roca Fabregat, Pedro; Molins Borrell, Climent
    International Masonry Conference
    p. 1-10
    Presentation's date: 2014-07-08
    Presentation of work at congresses

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    Micro-modeling techniques for the simulation of masonry are a valuable tool, when combined with nonlinear constitutive laws, for the investigation of the behavior of structural masonry. Through the simulation of the behavior of the materials locally up to and beyond failure, it is possible to evaluate the global behavior of the structure under a variety of loads. While the strength of the masonry joints and the unit-mortar interface in tension and shear can be fairly easily described in terms of frictional and tensile strength parameters, the compressive strength of the joints, and by extension the masonry composite, are more difficult to estimate a priori. For this reason, in the present paper a detailed micro-modeling approach in which units, mortar and their interface are modeled as separate parts, is proposed for the estimation of the compressive strength and the Young¿s modulus of the masonry composite. The approach proposed is based on well-known material and geometrical models. In addition, an analytical model for the estimation of the strength and the Young¿s modulus of masonry is also presented. A number of experimental case studies of masonry in compression reproduced using micro-modeling techniques are presented. The group of simulated cases consists of solid clay bricks and lime/cement mortar arranged in stack and running bond. A satisfactory comparison is obtained between the experimental values and the predictions of the FE and numerical micro-modeling methods proposed.

    Micro-modeling techniques for the simulation of masonry are a valuable tool, when combined with nonlinear constitutive laws, for the investigation of the behavior of structural masonry. Through the simulation of the behavior of the materials locally up to and beyond failure, it is possible to evaluate the global behavior of the structure under a variety of loads. While the strength of the masonry joints and the unit-mortar interface in tension and shear can be fairly easily described in terms of frictional and tensile strength parameters, the compressive strength of the joints, and by extension the masonry composite, are more difficult to estimate a priori. For this reason, in the present paper a detailed micro-modeling approach in which units, mortar and their interface are modeled as separate parts, is proposed for the estimation of the compressive strength and the Young’s modulus of the masonry composite. The approach proposed is based on well-known material and geometrical models. In addition, an analytical model for the estimation of the strength and the Young’s modulus of masonry is also presented. A number of experimental case studies of masonry in compression reproduced using micro-modeling techniques are presented. The group of simulated cases consists of solid clay bricks and lime/cement mortar arranged in stack and running bond. A satisfactory comparison is obtained between the experimental values and the predictions of the FE and numerical micro-modeling methods proposed.

  • Masonry material characterization methodology for micro-modeling

     Drougkas, Anastasios; Roca Fabregat, Pedro; Molins Borrell, Climent; Alegre Heitzmann, Vicente
    International Masonry Conference
    p. 1-7
    Presentation's date: 2014-07-08
    Presentation of work at congresses

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    Numerical and analytical micro-modeling of masonry structures requires knowledge of several elasticity and strength parameters of the constituent materials of the composite. Furthermore, when dealing with specimens produced in the lab or extracted from existing structures, several problems arise concerning the limited number of samples and to their dimension ratios which will often render them inappropriate for accurate standardized testing. In the case of historical structures, the number of samples may be limited due to the need for compliance with conservation principles. This paper proposes a methodology for the experimental derivation of several material parameters of the units, the mortar and the masonry composite from a limited amount of sampled material using conventional mechanical tests. The method attempts to alleviate some of the obstacles often encountered in the experimental characterization of masonry structures, and focuses on those parameters that are most important for the simulation of masonry under compression using micro-modeling techniques. The applicability of the proposed methodology in actual existing structures is demonstrated through a case study.

  • Monolithic concrete off-shore floating sturcture for wind turbines

     Molins Borrell, Climent; Campos Hortigüela, Alexis; Sandner, Frank; Matha, Denis
    European Wind Energy Association¿s (EWEA) Annual Conference
    p. 107-111
    Presentation's date: 2014-03-12
    Presentation of work at congresses

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    A new concept of a SPAR floating platform is being developed in the KIC-Innoenergy project AFOSP (Alternative Floating Platform Designs for Offshore Wind Turbines using Low Cost Materials). Members of the consortium are Gas Natural Fenosa, University of Stuttgart and Universitat Politècnica de Catalunya. The main differentiating aspects with respect to other SPAR prototypes are the monolithic nature of the whole structure, including both, the platform and the tower, the use of post-tensioned concrete as main material and the installation process. A comparison between similar steel and concrete designs demonstrates that the material cost for the concrete structure is around one third of the steel one. Considering that the concrete Oil & Gas platforms are virtually free of maintenance and have an extended lifetime, the real cost is less than 1/3 of the steel one, while the offshore tasks and the moorings systems have similar costs for both alternatives. Following a hydrostatic pre-design of the structure, coupled aero-servo-hydro-elastic analyses for a 5MW wind turbine have been performed by using an in-house FOWT model with a reduced number of degrees of freedom (DOF) and simplified aero- and hydrodynamics. With the obtained loads, the most relevant structural members have been checked, including a simplified fatigue limit state analysis, obtaining a lifetime over 50 years. Finally, a comprehensive cost analysis has been performed to obtain the Levelized Cost Of Energy (LCOE) for the developed platform.

    A new concept of a SPAR floating platform is being developed in the KIC-Innoenergy project AFOSP (Alternative Floating Platform Designs for Offshore Wind Turbines using Low Cost Materials). Members of the consortium are Gas Natural Fenosa, University of Stuttgart and Universitat Politècnica de Catalunya. The main differentiating aspects with respect to other SPAR prototypes are the monolithic nature of the whole structure, including both, the platform and the tower, the use of post-tensioned concrete as main material and the installation process. A comparison between similar steel and concrete designs demonstrates that the material cost for the concrete structure is around one third of the steel one. Considering that the concrete Oil & Gas platforms are virtually free of maintenance and have an extended lifetime, the real cost is less than 1/3 of the steel one, while the offshore tasks and the moorings systems have similar costs for both alternatives. Following a hydrostatic pre-design of the structure, coupled aero-servo-hydro-elastic analyses for a 5MW wind turbine have been performed by using an in-house FOWT model with a reduced number of degrees of freedom (DOF) and simplified aero- and hydrodynamics. With the obtained loads, the most relevant structural members have been checked, including a simplified fatigue limit state analysis, obtaining a lifetime over 50 years. Finally, a comprehensive cost analysis has been performed to obtain the Levelized Cost Of Energy (LCOE) for the developed platform.

  • Enginyeria de la construcció

     Molins Borrell, Climent
    Date of publication: 2014-02-01
    Book chapter

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  • Grup de tecnologies d'estructures

     Aguado De Cea, Antonio; Aparicio Bengoechea, Angel Carlos; Bairan Garcia, Jesus Miguel; Blanco Álvarez, Ana; Casas Rius, Joan Ramon; Chacon Flores, Rolando Antonio; de la Fuente Antequera, Alberto; Duarte Gomez, Noemi; Garcia Vicente, Tomas; Mirambell Arrizabalaga, Enrique; Molins Borrell, Climent; Oller Ibars, Eva; Pelà, Luca; Pialarissi Cavalaro, Sergio Henrique; Pujadas Alvarez, Pablo; Ramos Schneider, Gonzalo; Real Saladrigas, Esther; Roca Fabregat, Pedro; Santos Ferreira, Denise Carina; Segura Pérez, Ignacio; Turmo Coderque, Jose; Mari Bernat, Antonio Ricardo
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  • Método de doble punzonamiento de tracción indirecta para concreto reforzado con fibra: Ensayo Barcelona

     Aire, Carlos; Aguado De Cea, Antonio; Molins Borrell, Climent
    Date of publication: 2013-12-10
    Book

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    The present work describes the results of an experimental investigation on the performances of concrete specimens reinforced with steel fibers using the double punch test (DPT). The DPT is an indirect tensile test based on the configuration of double-punch test, named, Barcelona test that was developed for the systematic control of fiber reinforced concrete. DPT can be carried out by testing 150 × 150 mm concrete cylinders subjected to double punching test. Previous experimental results have showed that DPT gives significantly lower variability compared to other test methods. In the test performed, indirect tensile strength and fracture toughness result obtained by DPT were compared using molded cylinder and core concrete specimens.

  • Ensayo de doble punzamiento para caracterizar concreto reforzado con fibra. Nuevo método: ensayo Barcelona

     Aire, Carlos; Molins Borrell, Climent; Aguado De Cea, Antonio
    Congreso Nacional de Ingeniería Civil
    Presentation's date: 2013-11-27
    Presentation of work at congresses

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  • Development of a probabilistic model for the prediction of building damage due to tunneling induced settlements

     Camos Andreu, Carles; Molins Borrell, Climent; ¿packová, Olga; Straub, Daniel
    International Symposium on Geotechnical Safety and Risk
    p. 485-491
    Presentation's date: 2013-11
    Presentation of work at congresses

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    Tunnel construction can cause deformations of the surrounding ground, which endanger buildings and other structures located in the vicinity of the tunnel. The prediction of these deformations and the damages to the buildings is difficult due to limited knowledge of the geotechnical conditions and uncertainty in the response of the structures to the settlements. This paper presents a probabilistic model for prediction of the damage to buildings due to tunneling, which combines the volume loss method with the equivalent beam model. It furthermore proposes a probability-based method for determination of the limiting value of settlement that is used for control purposes during the tunnel construction. Updating of the limiting settlement with measurements gathered during the construction is described. The proposed methodology is applied to a masonry building affected by the construction of the L9 metro line tunnel in Barcelona.

  • Studies and repair of the railway bridge of Soller in Mallorca

     Molins Borrell, Climent
    International Conference on Arch Bridges
    p. 581-588
    Presentation's date: 2013-10-03
    Presentation of work at congresses

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    The studies and the repair works that were carried out on the railway bridge of Monts Reials in Sòller, which is the main city in the north-west coast of Mallorca , are described. The bridge presents five barrel vaults spanning eight meters with a width of 3.6 m and a depth of 0.60 m. The bridge was in a general good condition except for the first arch which presented some significant cracks, including very wide transversal cracks close to the abutments and spalling of the brick fabric just under the key of the arch. The assessment of the arch included the review of design documentation, full geometrical characterization of the arch, dynamic load tests and finite element analysis to check the capacity of the arch and interpret the causes of the damage. Repair works consisted of grouting of the arch ring, particularly in the cracks, repointing of the intrados of the barrel vault and the voussoirs and a watertight layer on the extrados.

    The studies and the repair works that were carried out on the railway bridge of Monts Reials in Sòller, which is the main city in the north-west coast of Mallorca , are described. The bridge presents five barrel vaults spanning eight meters with a width of 3.6 m and a depth of 0.60 m. The bridge was in a general good condition except for the first arch which presented some significant cracks, including very wide transversal cracks close to the abutments and spalling of the brick fabric just under the key of the arch. The assessment of the arch included the review of design documentation, full geometrical characterization of the arch, dynamic load tests and finite element analysis to check the capacity of the arch and interpret the causes of the damage. Repair works consisted of grouting of the arch ring, particularly in the cracks, repointing of the intrados of the barrel vault and the voussoirs and a watertight layer on the extrados.

  • Access to the full text
    Micro-modeling of stack bond masonry in compression using a plasticity law  Open access

     Drougkas, Anastasios; Molins Borrell, Climent; Roca Fabregat, Pedro
    International Conference on Computational Plasticity Fundamentals and Applications
    p. 919-928
    Presentation's date: 2013-09
    Presentation of work at congresses

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    A set of experimental tests to determine the compressive strength of masonry stack prisms has been numerically simulated using a combined plasticity-smeared crack constitutive law employed in three-dimensional analysis. Supported by an experimental campaign for the mechanical characterization of lime mortar masonry, a series of finite element analyses was performed in an attempt to assess the capacity of the model to reproduce the results obtained in terms of capacity, failure mode and global stiffness. The constitutive law used for the non-linear analysis of the masonry is a combination of a smeared cracking model in tension and a pressure dependent plasticity model in compression, which is capable of accounting for all failure mechanisms that may arise in concentric compression of masonry, both in the units and in the mortar. The purpose of this investigation is to establish whether a numerical approach based on the micro-modeling method is suitable for the simulation of the salient features encountered in masonry under compression as well as highlighting the main material properties necessary to be determined in order to properly model such experiments. The results are expanded upon through a parametric investigation.

  • Study of the sensitivity of different building structures to tunneling induced settlements

     Molins Borrell, Climent; Camos Andreu, Carles
    International Conference on Structures and Architecture
    p. 704-711
    Presentation's date: 2013-07-24
    Presentation of work at congresses

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    The sensitivity of urban buildings to tunneling induced settlements can vary according to the structural types and building materials. Very few studies deal with this particular field and, for design purposes, heuristic approaches are applied based on the studies developed in UK in the 1970's. From the statistical results of a sample of buildings located over the influence zones of the L9 metro line in Barcelona, three types of structures were devised to include most of them: (1) pure masonry buildings, (2) buildings combining masonry bearing walls and RC slabs and (3) buildings with RC structural frame with masonry infill. The paper discusses the numerical simulation of such structural types in service conditions and presents the particular phenomena (cracking of masonry and concrete, gapping between masonry walls and the RC beams or columns) that should be taken into account to assess the sensitivity of these buildings to tunneling settlements.

    he sensitivity of urban buildings to tunneling induced settlements can vary according to the structural types and building materials. Very few studies deal with this particular field and, for design purposes, heuristic approaches are applied based on the studies developed in UK in the 1970's. From the statistical results of a sample of buildings located over the influ- ence zones of the L9 metro line in Barcelona, three types of structures were devised to include most of them: (1) pure masonry buildings, (2) buildings combining masonry bearing walls and RC slabs and (3) buildings with RC structural frame with masonry infill. The paper discusses the numerical simulation of such structural types in service conditions and presents the particular phenomena (cracking of masonry and concrete, gapping between masonry walls and the RC beams or columns) that should be taken into account to assess the sensitivity of these buildings to tunneling settlements.

  • A 3D temporal evolutionary numerical model of a masonry building in Barcelona subjected to tunnelling subsidence

     Camos Andreu, Carles; Molins Borrell, Climent
    International Conference Computational Methods in Tunneling and Subsurface Engineering
    p. 495-506
    Presentation's date: 2013-04-17
    Presentation of work at congresses

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    The aim of this work is to deepen the knowledge of the numerical simulation used in the prediction of building damage produced by tunnelling subsidence. This paper analyzes the structural response of a one-storey building subjected to real ground movements experienced during the construction of the L9 Metro line tunnel in Barcelona, bored by a Earth Pressure Balance Machine (EPB) Tunnel Boring Machine (TBM). A 3D temporal evolutionary numerical model is used to predict the damage in the building resulting from tunnelling subsidence. The real structural damage presented is compared with the predictions of the numerical model. This last task can be done since the measures of real ground movements given by the monitoring instruments, such as retro-reflective prisms and total stations, are available for this research. Main model parameters have been determined by means of characterization experiments developed on the site and in the laboratory, thus giving a higher significance to the analysis.

    The aim of this work is to deepen the knowledge of the numerical simulation used in the prediction of building dam age produced by tunnel ling subsidence. This paper analyzes the structural response of a one-storey building subjected to real ground movements experienced during the construction of the L9 Metro line tunnel in Barcelona, bored by a Earth Pressure Balance Machine (EPB) Tunnel Boring Machine (TBM). A 3D temporal evolutionary numerical model is used to predict the damage in the building resulting from tunnelling subsidence. The real structural damage presented is compared with the predictions of the numerical model. This last task can be done since the measures of real ground movements given by the monitoring instruments, such as retro -reflective prisms and total stations, are available for this research. Main model parameters have been determined by means of characterization experiments developed on the site and in the laboratory, thus giving a higher significance to the analysis.

  • IDENTIFICACION DE PARAMETROS MECANICO-RESISTENTES EN OBRA DE FABRICA ESTRUTURAL

     Molins Borrell, Climent; Pelà, Luca; Gil Espert, Lluis; Cornado Bardon, Cossima; Serrà Martín, Isabel; Diaz Gomez, Cesar; Elyamani Ali Mohamed ., Ahmed; Camos Andreu, Carles; Roca Fabregat, Pedro
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  • Enginyeria de la Construcció

     Molins Borrell, Climent
    Date of publication: 2013-01
    Book chapter

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  • AFOSP ¿ WP1: analysis of the state of the art

     Molins Borrell, Climent
    Date: 2012-12-17
    Report

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  • Ensayo de doble punzonamiento (ensayo Barcelona) para caracterizar el comportamiento del hormigón reforzado con fibra

     Aire, Carlos; Aguado De Cea, Antonio; Molins Borrell, Climent
    Congreso Internacional y Reunión Técnica Asociación Argentina de Tecnología del Hormigón
    p. 335-342
    Presentation's date: 2012-11-07
    Presentation of work at congresses

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    Tradicionalmente, para caracterizar el comportamiento del hormigón reforzado con fibra se realizan ensayos de flexotracción en vigas. Sin embargo, existen otros procedimientos que debido a la complejidad y variabilidad de sus resultados no son considerados como procedimientos sistemáticos de control. Recientemente, se desarrolló un nuevo método llamado ensayo Barcelona, como una alternativa para determinar la resistencia a tracción indirecta del hormigón reforzado con fibra. Es un ensayo de fácil ejecución mediante el cual un cilindro de 150 mm de diámetro y 150 mm de altura, se someten a ensayo de doble punzonamiento. El método permite obtener la resistencia a tracción del hormigón confinado con fibra con coeficientes de variación menor a los obtenidos por otros métodos. Este artículo presenta un estudio comparativo entre los resultados de resistencia y tenacidad aplicando el ensayo Barcelona y el de Flexotracción.

  • Numerical simulation of the structural behaviour of buildings under tunnelling settlements: a case study in the L9 metro line (Barcelona)

     Camos Andreu, Carles; Molins Borrell, Climent; Arnau Delgado, Oriol; Gálvez, Javier
    International Conference on Structural Analysis of Historical Construction
    p. 432-440
    Presentation's date: 2012-10-15
    Presentation of work at congresses

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  • A new approach on crushing strength test for fibre reinforced concrete pipes

     Domingues de Figueiredo, Antonio; de la Fuente Antequera, Alberto; Molins Borrell, Climent; Aguado De Cea, Antonio
    RILEM International Symposium on Fibre Reinforced Concrete
    p. 1-13
    Presentation's date: 2012-09-21
    Presentation of work at congresses

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  • Fibre reinforced concrete pipes: new designing trends

     de la Fuente Antequera, Alberto; Domingues de Figueiredo, Antonio; Aguado De Cea, Antonio; Molins Borrell, Climent; Campos Escariz, Renata
    RILEM International Symposium on Fibre Reinforced Concrete
    p. 1-12
    Presentation's date: 2012-09-21
    Presentation of work at congresses

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  • An attempt to the determination of the partial safety factor for SFRC members subjected to bending forces

     Camos Andreu, Carles; Casas Rius, Joan Ramon; Molins Borrell, Climent
    RILEM International Symposium on Fibre Reinforced Concrete
    p. 1-10
    Presentation's date: 2012-09-20
    Presentation of work at congresses

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    In the last few years, research on techniques that permit the reduction or even the complete elimination of structural bar reinforcements has been intensified. The addition of steel fibres to the concrete matrix is proven to be an effective way of covering the deficiencies in this material when subjected to tensile stress. However, there still exists uncertainty surrounding some of the basis of design of structural members in ultimate condition. A clear example is the partial safety factor applied to the tensile strength. In this paper, a reliability-based analysis is carried out through the study of a particular application, such as the tunnel lining concrete segments built in an experimental section of the L9 Metro tunnel in Barcelona, solely reinforced with steel fibres. Specimens were extracted from three different segments and tested in tension by using the Barcelona test. Such a representative sample of tensile strength results made possible an assessment of the degree of the existing safety in this particular case by applying the reliability method FORM. The reliability analysis suggested a partial factor equal to 1.77. This would represent a first step to obtain the general material safety factor, which may involve a calibration in a wide range of tunnel segments and afterwards, other structural members and applications of SFRC.

  • Numerical tool for modeling steel fiber reinforced concrete

     Molins Borrell, Climent; Pros Parés, Alba; Diez Mejia, Pedro
    RILEM International Symposium on Fibre Reinforced Concrete
    p. 1-9
    Presentation's date: 2012-09-20
    Presentation of work at congresses

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    Steel Fiber Reinforced Concrete (SFRC) allows overcoming brittleness and weakness in tension, the main drawbacks of plain concrete. The goal of the present presentation is to present an ad-hoc numerical strategy to account for the contribution of the fibers in the simulation of the mechanical response of SFRC. In the model presented, the individual fibers immersed in the concrete bulk are accounted for in their actual location and orientation. The selected approach is based on the ideas introduced in the Immersed Boundary (IB) methods. These methods were developed to account for 1D (or 2D) solids immersed in 2D (or 3D) fluids. Here, the concrete bulk is playing the role of the fluid and the cloud of steel fibers is acting as the immerse boundary (that is a 1D structure in a 2D or 3D continuous). Thus, the philosophy of the IB methodology is used to couple the behavior of the two systems, the concrete bulk and the fiber cloud, precluding the need of matching finite element meshes. In the proposed approach, the meshes of the concrete bulk and fiber cloud are independent and the models are coupled imposing displacement compatibility and equilibrium of the two systems. The concrete bulk is modeled using any nonlinear model. The constitutive model for the fibers is designed to account for the complex interaction between fibers and concrete. The fiber models are based on previous investigations describing the concrete-fiber interaction and its dependence on the factors identified to be relevant: shape of the fiber (straight or hooked) and angle between the fiber and the crack plane. 3D examples with fibers distributed and oriented randomly are reproduced using the proposed approach.

  • Influence of fibre orientation on the performance of steel fibre-reinforced concrete

     Grünewald, Steffen; Laranjeira de Oliveira, Filipe; Walraven, Joost; Aguado De Cea, Antonio; Molins Borrell, Climent
    RILEM International Symposium on Fibre Reinforced Concrete
    p. 1-12
    Presentation's date: 2012-09-19
    Presentation of work at congresses

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    The performance of fibre-reinforced materials in the hardened state depends on the material behaviour, the production method and influences related to the structure. The position and the orientation of fibres in a structure can differ from the homogenous distribution and the random orientation in a mixer. Due to the flow of the concrete, fibres are able to orient which makes the prediction of the structural behaviour of fibre-reinforced concrete more complex, but it also offers the potential for an improved structural performance. Synergetic effects were observed with regard to flowable concrete related to the fibre efficiency. This paper discusses two studies on the effect of fibre orientation on the performance of steel fibre- reinforced concrete. The first study discusses the relation between fibre orientation and the distribution of fibre orientation. The analysis indicates that the variation of fibre orientation follows a Gaussian law and the distribution of fibre orientation can be predicted from the average fibre orientation. The second study on tunnel segments discusses the influence of production on the fibre orientation and how this affects the splitting tensile strength. The fibre orientation affects the fibre efficiency and the structural performance of steel fibre-reinforced concrete.

  • Q-00029

     Gironella i Cobos, Framcesc Xavier; Campos Hortigüela, Alexis; Molins Borrell, Climent; Roca Fabregat, Pedro; Mari Bernat, Antonio Ricardo
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  • Use of double punching test (Barcelona test) for quality control of fiber reinforced concretes

     Carmona Malatesta, Sergio Alejandro; Aguado De Cea, Antonio; Molins Borrell, Climent
    International Conference: Concrete in the Low Carbon Era
    p. 1-10
    Presentation's date: 2012-07
    Presentation of work at congresses

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    Traditionally, flexural testing is used to characterize the strength and post–peak behavior of fiber–reinforced concretes (FRC). Nevertheless, these tests results exhibit a high dispersion, and therefore invalidate their use as tests for the systematic control of FRCs in works. Also, they have the disadvantage of being complex tests, which require heavy specimens and highly qualified staff. With the aim to solve these problems, an indirect tensile test based on double punching test set up, called the Barcelona test, has been proposed to control tensile behavior of FRC. This test requires smaller specimens, with a high specific surface of fracture, allowing obtain values representative of strength and toughness of materials, with considerably less dispersion than other experimental methodologies, and was recently standardized in Spain. This paper presents the results of an experimental program, which validate the use of Barcelona test as a suitable methodology to systematic characterization FRC in works.

  • Structural Response of Precast Concrete Segmental Tunnel Linings  Open access

     Arnau Delgado, Oriol
    Department of Construction Engineering, Universitat Politècnica de Catalunya
    Theses

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    The increasing use of the tunnel boring machines (TBMs) has entailed their own evolution and the improvement of the construction processes applied, allowing the construction of tunnels on more complex hydro-geological conditions. These new drilling facilities imply that higher ground and water pressures have to be resisted by the structural lining, turning its design into a key item in all current tunnel projects. TBMs construction process is mainly associated to precast concrete segmental tunnel linings, which are consisted of concrete rings sequentially placed as the tunnel drilling advances. Despite segmental tunnel linings are widely used, their structural response presents significant uncertainties due to the particular configuration on multiple precast pieces and the evolutionary construction process applied. The improvement and optimization of segmental tunnel linings, necessary to obtain safer structures at a lower cost, requires a significant advance in the knowledge of their structural response and about the appropriate techniques to properly reproduce it. This PhD thesis present the mechanisms and phenomena involved in the structural response of precast concrete segmental tunnel linings, detailing numerical modeling strategies to properly simulate them. The integration of all these techniques in a unique model allows the analysis of a real tunnel lining subjected to different scenarios, determining the influence and relevance of the main parameters defining a tunnel and its structural lining. Present research departs from an innovative in situ test carried out at Line 9 subway tunnel in Barcelona. The treatment and analysis of the obtained data provides experimental evidences about the structural response of segmental tunnel linings and the main involved mechanisms and phenomena. Different numerical simulation strategies are developed in order to properly reproduce such mechanism and phenomena, achieving a reliable simulation of an isolated ring response. The longitudinal response of the segmental concrete linings is obtained through the detailed study of the construction process applied and the ground-structure interaction mechanisms. The knowledge of the longitudinal force present at a segmental tunnel lining is of paramount importance in order to determine the interaction degree between adjacent rings and the consequent three-dimensionality of the lining response. Finally, the numerical simulation of a real tunnel section subjected to different scenarios of load and boundary conditions determines the influence of the three-dimensional effects on segmental concrete linings response, concluding about its structural implications in respect to the isolated ring approach usually employed in design processes.

  • Proceso de sustitución o remoción de aerogenerador en estructuras flotantes monolíticas tipo SPAR

     Molins Borrell, Climent; Rebollo Pericot, Josep; Campos Hortigüela, Alexis
    Date of request: 2012-03-14
    Invention patent

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    Proceso de sustitución o remoción de aerogenerador en estructuras flotantes monolíticas tipo SPAR.

    La presente invención hace referencia al proceso de sustitución de un aerogenerador en una estructura flotante monolítica tipo SPAR fondeada.

    La invención se basa en la inundación controlada de la estructura flotante tal que la coronación de la estructura quede situada a una altura sobre el nivel medio del mar (NMM), entre 5 y 20 m, para que la coronación de la estructura y el aerogenerador sean fácilmente accesibles desde la cubierta de una embarcación tipo catamarán que se acople a la estructura y, mediante un sistema de puente grúa o similar, efectuar tareas de mantenimiento y/o sustitución sin necesidad de grúas flotantes. Finalizadas dichas tareas, la estructura se emerge mediante evacuación por bombeo del agua interior, permitiendo también reajustar la línea de flotación y la tensión en los amarres si las nuevas condiciones de masa lo requieren.

  • Numerical Approach For Modeling Steel Fiber Reinforced Concrete  Open access

     Pros Parés, Alba
    Universitat Politècnica de Catalunya
    Theses

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    One alternative to overcome the main drawbacks of plain concrete in tension (its brittleness and weakness) is Steel Fiber Reinforced Concrete (SFRC), a technique introduced in the 70's, which consists of adding steel fibers into the concrete matrix. Due to the presence of the steel fibers into the concrete matrix, the residual strength and the energy dissipation of the material increase. Moreover, once a crack appears in the concrete, the steel fibers sew this fissure. The shape, the length and the slenderness of the fibers influence on the SFRC behavior. Moreover, the distribution and the orientation of the fibers into the concrete domain must be taken into account for characterizing the material. In order to characterize the behavior of SFRC, a numerical tool is needed. The aim is to simulate the most standard and common tests (direct and indirect tension tests, flexural test, double punch tes,¿) and more complex setups. This thesis proposes a numerical tool for modeling SFRC avoiding homogenized models (not accurate enough) and conformal meshes (too expensive). Therefore, the numerical tool accounts for the actual geometry of the fibers, discretized as 1D bars nonconformal with the concrete bulk mesh (2D or 3D domains). The two materials, corresponding to the concrete bulk and the fiber cloud, are defined independently, but coupled by imposing displacement compatibility. This compatibility is enforced following the ideas of the Immersed Boundary methods. Two different models are considered for modeling the concrete bulk (a continuous one and a discontinuous one). The parametric study of each model is done for only plain concrete, before the addition of the steel fibers. A phenomenological mesomodel is defined for modeling steel fibers, on the basis of the analytical expressions describing the pullout tests. This phenomenological mesomodel not only describes the behavior of the steel fibers, but also accounts for the concrete-fiber interaction behavior. For each fiber, its constitutive equation is defined depending on its shape (straight or hooked) and the angle between the fiber and the normal direction of the failure pattern. Both 2D and 3D examples are reproduced with the proposed numerical tool. The obtained results illustrate the presence of the steel fibers into the concrete matrix. The shape of the fiber influences of the SFRC behavior: the residual strength is higher for hooked fibers than for straight ones. Moreover, increasing the quantity of fibers means increasing the residual strength of the material. The obtained numerical results are compared to the experimental ones (under the same hypothesis). Therefore, the proposed numerical approach of SFRC is validated experimentally.

  • Procedimiento de instalación y mantenimiento de estructura flotante monolítica para soporte de aerogenerador

     Molins Borrell, Climent; Rebollo Pericot, Josep; Campos Hortigüela, Alexis
    Date of request: 2012-02-10
    Invention patent

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    Proceso de instalación de estructura flotante monolítica para soporte de aerogenerador en zonas marítimas de gran profundidad y alejadas de la costa que consiste en el fondeo de la estructura desde una posición horizontal de transporte hasta la vertical mediante la inundación controlada de su interior, de forma que el tramo emergente sobre la superficie marina sea mínimo, para que el montaje del aerogenerador a instalar en la coronación se realice a través de una embarcación tipo catamarán o similar y sin necesidad de medios complementarios de elevación. El emergido de la estructura se realiza mediante extracción del agua interior a través de diversas válvulas a lo largo de la altura que se equilibra parcialmente con el lastre tipo granular introducido a través de una apertura lateral. La fuerza en los amarres de sujeción se aplica mediante el ajuste de la línea de flotación de la estructura.

  • Enginyeria de la construcció

     Molins Borrell, Climent
    Date of publication: 2012-01-31
    Book chapter

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    Tot i l'habitual creixement en potència i nuclis dels microprocessadors, l'any va tenir com a gran novetat l'estabilització del nou mercat dels telèfons intel·ligents (smartphones) i, sobre tot, de les "tauletes" (tablets), on diversos fabricants van començar a fer competència als iPhone i iPad d'Apple que ja van comercialitzar noves versions durant l'any 2011. També cal destacar que va crèixer de la idea de la "inf ormàtica verda" (green computing) respectuosa amb el medi ambient i, sobre tot, la força de les xarxes socials quasi ja del tot imprescindibles. Sense oblidar la desaparició, en poques setmanes, de tres personatges que han estat fonamentals en diversos aspectes de la informàtica moderna, ni els esforços d'Europa per estar al dia en el tema dels projectes de futur de les TIC. També és novetat l’arribada d’Amazon a Espanya, a partir de setembre d’enguany. Això suposa, entre d’altres coses, una empenta a la venda del seu lector de eBooks Kindle que es proposa com a regal nadalenc.

    Postprint (author’s final draft)

  • ESTRUCTURA FLOTANTE DE HORMIGÓN PREFABRICADO PARA SOPORTE DE AEROGENERADOR

     Molins Borrell, Climent; Rebollo Pericot, Josep; Campos Hortigüela, Alexis
    Date of request: 2011-12-23
    Invention patent

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    Estructura flotante de hormigón prefabricado para soporte de aerogenerador.

    La plataforma objeto de la presente invención se basa en una plataforma monolítica flotante de tipo SPAR, prefabricada en hormigón y precomprimida mediante armaduras activas.

    La estructura está formada por un tramo de geometría cilíndrica (13), que hace las funciones de elemento de flotación y otro superior, situado por encima de la superficie marina (12), de forma cilíndrica y/o troncocónica, que sirve para el soporte del aerogenerador.

    La fijación de la estructura al fondo marino se realiza mediante líneas 20 de cables, a través de elementos de lastre pesados o pilotes de succión (16), capaces de contrarrestar las componentes vertical y horizontal inducidas por los cables.

  • Clasificación de los tipos constructivos y estructurales de los edificios para el estudio de su sensibilidad frente a los efectos de la tunelación

     Serrà Martín, Isabel; Camos Andreu, Carles; Molins Borrell, Climent; Chirino Andalco, Mariel
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-9
    Presentation's date: 2011-10-26
    Presentation of work at congresses

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  • Efecto del ciclo de curado sobre el riesgo de fisuración de dovelas prefabricadas para revestimiento de túneles

     Crespo Garibay, María Delia; Mari Bernat, Antonio Ricardo; Molins Borrell, Climent
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-10
    Presentation's date: 2011-10-26
    Presentation of work at congresses

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    En esta ponencia se analiza el efecto del curado térmico sobre la evolución de las temperaturas, velocidades de calentamiento y enfriamiento, tensiones y resistencias de las dovelas de hormigón para revestimiento de túneles, a fin de determinar que ciclo de curado es el más ventajoso. Para la simulación numérica se utilizan los datos de caracterización térmica y mecánica obtenidos en base a resultados de ensayos del hormigón presentados con anterioridad [1]. El análisis térmico permite verificar si un ciclo determinado cumple con las reglas de buena práctica en lo que se refiere a temperaturas máximas alcanzadas dentro de la dovela, y velocidades máximas de calentamiento y enfriamiento. Finalmente, el análisis mecánico permite verificar hasta el riesgo que la dovela fisure, comparando la evolución de la relación tensión/resistencia efectiva en el punto que tiene mayor riesgo de fisuración. Ello permite determinar el ciclo térmico más adecuado para obtener una resistencia en un plazo dado.

  • Nuevas tendencias para el refuerzo óptimo de tubos de hormigón

     de la Fuente Antequera, Alberto; Aguado De Cea, Antonio; Molins Borrell, Climent; de Figueiredo, Antonio; Campos Escariz, Renata
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-10
    Presentation's date: 2011-10-27
    Presentation of work at congresses

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    Este artículo tiene como objetivo presentar las últimas investigaciones realizadas en referencia al uso de fibras en tubos de hormigón. En la primera parte del trabajo se presenta un estudio de su comportamiento en el ensayo de aplastamiento, haciendo hincapié tanto en los aspectos técnicos de su ejecución como en cuestiones relacionadas con la simulación numérica. En la segunda parte, se presentan los resultados experimentales obtenidos en ensayos mecánicos de tubos de hormigón con fibras de 600 mm, 800 mm y 1000 mm de diámetro. Éstos han servido para validar el modelo numérico MAP, permitiendo concluir que ésta es una herramienta adecuada para el análisis el diseño de este tipo de tubos. Asimismo, se presenta un procedimiento para hallar la cuantía de fibras necesaria en función de la clase resistente exigida.

  • Estudio de las cubetas de asientos producidas por la tunelación y simulación de la respuesta estructural de edificios afectados

     Camos Andreu, Carles; Arnau Delgado, Oriol; Molins Borrell, Climent; Alegre Heitzmann, Vicente
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-10
    Presentation's date: 2011-10-25
    Presentation of work at congresses

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    En el presente estudio se ha modelizado el comportamiento estructural de unos edificios afectados por los asientos producidos por la tunelación. Los valores reales de los asientos se comparan con los predichos mediante los métodos empíricos que estiman la forma y el área de la cubeta de asiento en función de las propiedades del terreno y de la supuesta pérdida de volumen inherente al método constructivo. Seguidamente se aplica el método de la viga equivalente para la predicción de los daños en los edificios afectados y se comparan con los daños reales. Finalmente se simula el comportamiento estructural de los edificios sometidos a los asientos medidos utilizando macro-modelos constitutivos ortótropos no lineales de obra de fábrica. De la comparación de los resultados numéricos con las lesiones y con las predicciones del método de la viga equivalente se extraen conclusiones relativas a la aplicación de dicho método simplificado.

  • Simulación numérica del hormigón reforzado con fibras de acero

     Pros Parés, Alba; Diez Mejia, Pedro; Molins Borrell, Climent
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-9
    Presentation's date: 2011-10-27
    Presentation of work at congresses

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    El Hormigón Reforzado con Fibras de Acero (HRFA) es una técnica que consiste en añadir fibras de acero en el hormigón. La forma, las dimensiones, la esbeltez, la orientación y la distribución de las fibras caracterizan el comportamiento del material. Para caracterizar y estudiar el HRFA, se han empleado distintos ensayos: de tracción directa e indirecta y de flexotracción. En esta ponencia se presenta un modelo simplificado para simular el acoplamiento fibra-hormigón mediante el cual es posible tener en cuenta el efecto real de cada una de las fibras individuales. Así, es posible obtener la respuesta resistente teniendo en cuenta el número real de fibras, su orientación y posición. Para poder tener en cuenta la interacción fibra-hormigón, las ecuaciones constitutivas de las fibras se basan en expresiones analíticas dependiendo del ángulo entre cada fibra y la fisura en el hormigón. El hormigón se modeliza considerando un modelo no lineal.

  • Nueva metodología para la evaluación de la orientación de las fibras

     Laranjeira de Oliveira, Filipe; de la Fuente Antequera, Alberto; Aguado De Cea, Antonio; Molins Borrell, Climent
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-10
    Presentation's date: 2011-10-27
    Presentation of work at congresses

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    En esta comunicación se presenta una nueva filosofía para determinar la orientación de las fibras. En primer lugar, se evalúa la orientación de la fibra en el dominio espacial a través de un enfoque probabilístico que proporciona una visión más amplia que el análisis 2D recogido en la literatura. Posteriormente, se estudia el efecto pared sobre la orientación de las fibras y se anticipa una nueva aproximación para su cuantificación, tanto en condiciones isótropas como anisótropas. Por último se presenta la estrategia paso a paso propuesta en este trabajo para evaluar la orientación de las fibras.

  • Respuesta estructural de los revestimientos de túnel realizados a base de dovelas prefabricadas frente a cargas localizadas

     Molins Borrell, Climent; Arnau Delgado, Oriol
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-10
    Presentation's date: 2011-10-27
    Presentation of work at congresses

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    La presente comunicación tiene por objetivo evaluar la respuesta estructural presentada por los revestimientos de túneles a base de dovelas prefabricadas frente a cargas localizadas. La capacidad de interacción entre anillos determinará el grado de tridimensionalidad de la respuesta del revestimiento y, en consecuencia, su rigidez y resistencia. La contribución estructural entre anillos adyacentes se analiza por medio de un modelo tridimensional de elementos finitos de tipo lámina que reproduce adecuadamente la respuesta de las juntas existentes en un tramo real de 11 anillos. El estudio de distintas condiciones de terreno envolvente y de tensión de compresión longitudinal permiten obtener conclusiones prácticas sobre la respuesta de los revestimientos de dovelas frente a cargas localizadas.

  • Simulación de los daños estructurales producidos por la tunelación en estructuras de obra de fábrica

     Arnau Delgado, Oriol; Molins Borrell, Climent; Barbosa, Bruno; Alegre Heitzmann, Vicente
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-10
    Presentation's date: 2011-10-27
    Presentation of work at congresses

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    La perforación de túneles genera subsidencias en el terreno que pueden causar daños en los edificios existente en superficie debido a los asientos diferenciales. Los edificios cuya estructura portante está formada por elementos continuos de obra de fábrica son los que suelen presentar una mayor afectación frente a este tipo de solicitaciones. Además, el complejo comportamiento material que la obra de fábrica presenta dificulta significativamente la simulación y predicción de la respuesta del edificio ante dichas acciones. En esta ponencia se muestra el proceso de modelización empleado en la simulación de un edificio real de obra de fábrica afectado por el colapso del túnel del Carmel (Barcelona). Los resultados de la simulación han presentado una muy buena correlación con los registros de daños reales, lo que permite concluir sobre la capacidad de los modelos empleados.

  • Comportamiento a tempranas edades de elementos de hormigón con restricción externa total

     Crespo Garibay, María Delia; Molins Borrell, Climent; Mari Bernat, Antonio Ricardo
    Congreso de la Asociación Científico-Técnica del Hormigón Estructural
    p. 1-10
    Presentation's date: 2011-10-26
    Presentation of work at congresses

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    Durante las primeras edades del hormigón se producen deformaciones termo-higrométricas las cuales, si son restringidas, sobre todo por coacciones externas, producen tracciones que pueden fisurar el hormigón. Un ejemplo típico es el caso de muros con empotramiento en su base. El objetivo del presente estudio es determinar las fuerzas que se producen en el momento de la fisuración en elementos con restricción total de las deformaciones a fin de poder analizar la exactitud de la hipótesis realizada en algunos códigos sobre el valor de los esfuerzos normales con los que se calcula la armadura mínima. Se realiza un estudio paramétrico a fin de distinguir la influencia que las diferentes variables (tipo de hormigón, tipo de encofrado, canto del elemento, edad de desencofrado) ejercen sobre el desarrollo de las temperaturas y tensiones dentro del elemento.

  • Nueva metodología para el diseño de tubos de hormigón estructural  Open access  awarded activity

     de la Fuente Antequera, Alberto
    Department of Construction Engineering, Universitat Politècnica de Catalunya
    Theses

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    The technical and economic suitability of using fibers has been proved in reinforced concrete pipes.However, the use of fibers in concrete pipe is slow, on the one hand due to the inertia to change in the construction field, and on the other hand due to the lack of a standardized, agile and reliable design method that accounts for the structural contribution of fibers. In this sense, this Doctoral Thesis aims to cover these aspects with regard to reinforced concrete pipes. For this purpose, a design method allows considering the strength contribution of the fibers in concrete pipes is proposed. Furthermore, in order to favour the spread of the results both to the scientific and the industrial community, the document of the Doctoral Thesis is presented as a compendium of articles accepted and / or in review status in scientific journals. Each of these articles presents the results of each of the lines of work and whose union has helped to achieve the main objective of this Doctoral Thesis. Firstly, the numerical tool Analysis of Evolutionary Sections (AES) developed to deal with the analysis of the strength response of reinforced concrete sections is presented. The tool is general and can simulate different reinforcement configurations (passive and/or active reinforcement with the possibility of incorporating fibers) and even the evolutionary construction of the section taking into account the rheological behaviour of materials. The model AES was subsequently used as a calculation tool of sections with the aim of addressing parametric studies as well as a subroutine into the other two models developed in the scope of this Doctoral Thesis. The second line of work focuses on the study of conventional reinforced concrete pipes. To address their optimal design the model Análisis de Tubos de Hormigón (ATH) has been developed. The practical interest of the model lies in the possibility of obtaining the optimal amount of reinforcement which meets the requirements in terms of bearing capacity specified in project. These reinforcements obtained from the models are, in most of the cases, inferior to the amounts in the design tables that are used traditionally. With the purpose of confirming the suitability of the ATH, an experimental campaign with tubes of 2800 mm of diameter has been carried out. By using the model, reductions up to 30% of the reinforcement have been obtained for pipes with the aforementioned diameter, while the differences in the bearing capacity do not exceed 10% when compared to the results of the three bearing edge test performed in the laboratory. The third and final line of work deepens into the technical and industrial side of the fiber reinforced concrete pipes. On the one hand, an extensive experimental campaign (some of it developed at the Universidade de São Paulo) is conducted, addressing issues associated with fiber reinforced concrete as well as others regarding the three edges test and the structural response of tubes of different diameters and with different amounts of fibers. On the other hand, the model for the Analysis of Pipes (MAP) was developed simultaneously for simulating the structural response of the fiber reinforced concrete pipes. The results of the bearing capacity of tubes up to 1000 mm of diameter tested have been compared with simulations performed with the MAP model, obtaining excellent correlations and not exceeding, in any case, the 5.5% relative error between the design loads. In view of the good results, it can be concluded that the design methodology herein presented, based on the use of the MAP model, ensures results that fit real behaviour and that the amounts of reinforcement provided are very close to the optimum necessary to meet the strength requirements established in each case.

    El hormigón reforzado con fibras ha demostrado ser una alternativa atractiva frente al hormigón armado tradicional en numerosas tipologías estructurales. En los últimos diez años, los avances técnicos llevados a cabo en relación con este material han sido muy importantes, prueba de ello es que varios códigos normativos nacionales a nivel europeo ya han aceptado las fibras estructurales como material de refuerzo del hormigón, entre ellos la instrucción española EHE‐08 “Instrucción de Hormigón Estructural” en su Anejo 14. A pesar del escenario aparentemente positivo, la consideración de aporte resistente asociado al uso de las fibras es todavía anecdótica, lo cual no responde en la mayoría de las ocasiones a razones técnicas, sino a la gran inercia al cambio existente en el sector general de la construcción. Este es el caso de las tuberías de hormigón armado para redes de saneamiento. Se trata de una tipología estructural para la cual la idoneidad técnica y económica del uso de fibras ya se ha demostrado. Asimismo, también ha sido regulado por varias normativas nacionales específicas de tubos, entre éstas, la UNE‐EN 1916:2008 “Tubos y piezas complementarias de hormigón en masa, hormigón armado y hormigón con fibra de acero”. Sin embargo, el empleo de forma natural de fibras en tubos de hormigón está siendo lento, por una parte, debido a la inercia al cambio anteriormente citada, a lo que debe sumarse el hecho que pocas de las varias experiencias llevadas a cabo se han plasmado en la literatura técnica, y, por otra, a que no existe un método de diseño estandarizado, ágil y fiable al alcance de los proyectistas que permita tener en cuenta la incorporación de las fibras como material resistente. En esta dirección, la presente Tesis Doctoral tiene como objetivo cubrir estos aspectos asociados con los tubos de hormigón armado. Para ello, los trabajos llevados a cabo han permitido lograr distintos avances en relación con los tubos de hormigón armado tradicionales y los tubos de hormigón armado con fibras. Respecto a estos últimos, se propone el primer método para el diseño conocido hasta la fecha y que permite considerar la contribución resistente de las fibras. Además, de cara a maximizar la difusión de los resultados tanto hacia la comunidad científica como hacia la industrial, el documento de Tesis se plantea como un compendio de artículos aceptados y/o en estado de revisión en revistas científicas en los que se recogen los resultados específicos de cada una de las partes, cuya unión, ha permitido alcanzar el objetivo principal de esta Tesis Doctoral.

  • Memoria técnica módulo divisorio de 6,00 m de altura

     Molins Borrell, Climent; Mirambell Arrizabalaga, Enrique
    Date: 2011-09-29
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  • Memoria técnica módulo divisorio de 5,00 m de altura

     Molins Borrell, Climent; Mirambell Arrizabalaga, Enrique
    Date: 2011-09-30
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  • Discrete meso-modeling of steel fiber reinforced concrete: simulation of flexural behavior

     Pros Parés, Alba; Diez Mejia, Pedro; Molins Borrell, Climent
    International Conference on Computational Plasticity
    p. 1-8
    Presentation's date: 2011-09-08
    Presentation of work at congresses

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  • Numerical simulation of the structural damages produced on masonry buildings by tunnelling induced settlements

     Molins Borrell, Climent; Arnau Delgado, Oriol; Barbosa, Bruno; Alegre Heitzmann, Vicente
    International Conference on Computational Plasticity Fundamentals and Applications
    p. 1
    Presentation's date: 2011-09-07
    Presentation of work at congresses

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