• Informe de resultados. Fabricación y caracterización de hormigones H30 y H50

  (2015). IT644

  
  

  Abstract

  En el presente documento se describen los procedimientos utilizados y resultados obtenidos en los ensayos realizados para la caracterización mecánica de dos hormigones de resistencias características a compresión de 30 MPa (H30) y 50 MPa (H50). La caracterización mecánica de los hormigones ha consistido en la determinación de las resistencias a compresión, tracción indirecta y cortante, la determinación del módulo secante de elasticidad en compresión y la determinación del comportamiento tensión-deformación del material hasta rotura. La fabricación de las muestras de ensayo y ejecución de los ensayos se ha realizado en el Laboratori de Tecnologia d’Estructures Luis Agulló (LTE).

  Abstract
  En el presente documento se describen los procedimientos utilizados y resultados obtenidos en los ensayos realizados para la caracterización mecánica de dos [...]

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• Higher-Order Simulations: Strategic Investment under Model-Induced Market Structures

  G. Peffer, B. Llacay

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2004). 12

  
  

  Abstract

  The trading and investment decision processes in financial markets becomes ever more dependent on the use of valuation and risk models. In certain, cases such as risk management, modelling practice has become so homogeneous that one is led to ask about the effect this has on the price formation process. Furthermore, should stable price patterns emerge from this, can sophisticated investors who have private information about the use and characteristics of these models make superior gains? The aim of this article is to test this hypothesis in a stylised market environment, where a strategic trader who trades on information about the valuation and risk management models used by competitors. Results show that for our particular market setting, such a strategy has an advantage over those that do not use this information.

  Abstract
  The trading and investment decision processes in financial markets becomes ever more dependent on the use of valuation and risk models. In certain, cases such as risk management, [...]

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• Implementation of an Automated Benchmarking module for Kratos

  F. Mossaiby

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2009). 11

  
  

  Abstract

  The steady and careful checking process of the test examples is almost impossible for developers and users of Kratos, and needs to be automated. This has been the inspiration of development of an Automated Benchmarking module. During the nightly builds of Kratos, which will be done on the upcoming Kratos server, this module automatically runs all test examples and verifies the results against a reference data set. It will send an email containing the status of each test example to a list of recipients. This can be useful in several ways. First, it will be clear when a conflict has occurred. This will help greatly to find the user committed the changes, ask him / her to correct / undo it. Also, it will let other users to be aware of a conflict in the latest code base, and avoid updating their own local code base, before it has been corrected. This can save them a lot of time and effort.

  Abstract
  The steady and careful checking process of the test examples is almost impossible for developers and users of Kratos, and needs to be automated. This has been the inspiration [...]

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• Simulador de voladura en macizos rocosos

  C. Labra, F. Zárate

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2012). 10

  
  

  Abstract

  Se presenta la formulación básica para la modelación de voladura en macizos rocosos mediante el MED. El modelo presentado muestra las características esperadas para este tipo de simulaciones. La condición del explosivo debe ser estudiada con más detalle para asegurar la relación entre los valores característicos de la condición y un explosivo determinado. Se establecen las condiciones requeridas para el modelo 2D, pudiendo ser extendidas durante el proyecto a la versión 3D. Se han desarrollado las interfaces de usuarios completamente funcionales tanto para 2D como 3D, denominando al software BLAST, con su respectivo manual de instrucciones Se presenta además un estudio del efecto de las cargas explosivas en 2D, donde se aprecia el comportamiento del macizo rocoso para distintos niveles de carga, los cuales están directamente relacionados con el explosivo utilizado, además de todas las consideraciones operacionales que puedan ser consideradas por el operario, como el diámetro del barreno o posibles cámaras de aire para desacoplar el explosivo.

  Abstract
  Se presenta la formulación básica para la modelación de voladura en macizos rocosos mediante el MED. El modelo presentado muestra las características [...]

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• Estudio de la seguridad de presas e identificación de escenarios de riesgo mediante sistemas inteligentes (SEPRISIS)

  J. Miquel, J. González

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2011). 9

  
  

  Abstract

  El proyecto SEPRISIS tiene como objetivo el desarrollo de sistemas inteligentes basados en redes neuronales, para analizar el comportamiento de una presa, y con ello prever e identificar escenarios de riesgo. Dichos sistemas inteligentes servirán por tanto, como herramienta de soporte a la toma de decisiones.

  Abstract
  El proyecto SEPRISIS tiene como objetivo el desarrollo de sistemas inteligentes basados en redes neuronales, para analizar el comportamiento de una presa, y con ello prever [...]

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• Interfaces 3DShell y 3DSolid. GiD-Sap2000

  F. Muñoz, J. Meza, F. Peña

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2012). 8

  
  

  Abstract

  Este documento se ha diseñado a partir de la interfaz GiD-Sap90 y lo que pretende es hacer una actualización de esta metodología aplicada a las últimas versiones del GiD (Versión 10) y Sap2000 (versiones 12 y 14). Este trabajo se ha llevado a cabo entre investigadores del Instituto de Ingeniería de la UNAM y la Escuela Técnica Superior de Arquitectura del Valles y Barcelona de la U.P.C. Esta actualización incorpora una doble interfaz. Lo que se pretende es que el usuario continúe trabajando en GiD todo el preproceso para la generación de modelos numéricos de geometría compleja y pueda exportar a Sap2000 el archivo para su análisis. Una vez ahí, el usuario puede decidir si continua analizando el modelo dentro de Sap2000 o regresar a GiD mediante esta interfaz para visualizar los resultados en GiD. Estas interfaces son herramientas muy potentes para los usuarios que se dedican a analizar estructuras complejas como lo son los edificios históricos, ya que GiD y su preproceso ha sido creado para trabajar y estructurar mallas sofisticadas geométricamente. Además, esta interfaz le permite al usuario incorporar, dentro de GiD, todas las condiciones que Sap2000 requiere para el análisis numérico de una estructura. En resumen, estas interfaces permiten agilizar el análisis numérico de estructuras complejas como lo son los edificios históricos.

  Abstract
  Este documento se ha diseñado a partir de la interfaz GiD-Sap90 y lo que pretende es hacer una actualización de esta metodología aplicada a las últimas [...]

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• Simulación del comportamiento al fuego de paneles de lana de roca

  D. Capua

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2011). 6

  
  

  Abstract

  En este trabajo se presenta el informe correspondiente al estudio del comportamiento bajo la acción del fuego de un panel de lana de roca fabricado por la empresa de prefabricados Pretersa-Prenavisa. La referencia de la pieza a estudiar es PANEL DE 20 CON LANA DE ROCA           con una longitud de 10m. El objetivo final es analizar la estabilidad global del panel sometido a la acción del fuego. Dicha estabilidad global puede verse comprometida si las deformaciones térmicas son suficientemente grandes como para que el panel salga fuera del pilar de borde que le confiere estabilidad lateral.

  Abstract
  En este trabajo se presenta el informe correspondiente al estudio del comportamiento bajo la acción del fuego de un panel de lana de roca fabricado por la empresa de [...]

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• SIMPACT: Explicit Dynamic Code for non Linear Structural Analysis

  R. Otín

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2009). 5

  
  

  Abstract

  SIMPACT is a finite element computer system developed at the International Center for Numerical Methods in Engineering (CIMNE) in Barcelona, Spain, for analysis of structures subjected to dynamic and impact loading. Typical application of SIMPACT include among others the seismic analysis of structures, the study of structures subjected to internal of external vibrations, the prediction of ship motions originated by waves crashworthiness studies in automobiles, aerospace and maritime vehicles, analysis of structures subjected to blast pressure loading and a wide range of impact problems typical of defense applications.

  Abstract
  SIMPACT is a finite element computer system developed at the International Center for Numerical Methods in Engineering (CIMNE) in Barcelona, Spain, for analysis of structures [...]

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• Cálculo de un depósito de hidrógeno

  M. Coma, A. Férriz, O. Fruitos Bickham, X. Martínez

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2010). 4

  
  

  Abstract
  Simulación realizada con FEMCOM 1.0. Modelos con elementos hexaedros. Proyecto “DIPH2”

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• Interfase GiD per a la generació paramètrica de geometries trenades per a l’apantallament de cables coaxials

  R. Méndez, R. Isanta, R. Otín, O. Fruitos

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2009). 3

  
  

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• Evaluating manoeuvering and seakeeping performance of a surface effect ship

  E. Oñate

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2012). 2

  
  

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• Estudio de un depósito de hidrógeno por el Método de los Elementos Finitos y validación analítica

  A. Férriz, O. Fruitos, M. Coma, S. Oller

  (2010). IT603

  
  

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• Research lines and software products for the oil and gas industry

  I. Informe

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2013). 1

  
  

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• Modeling thermoplastic melt spread over different flooring materials

  K. Butler, E. Oñate, R. Rossi, J. Marti, S. Idelsohn

  (2010). PI349

  
  

  Abstract

  The effects of the thermal properties of three flooring materials on the spread rate of polymer melt over the surface were studied using a model based on the Particle Finite Element Method (PFEM). The high thermal conductivity of steel keeps the steel floor at a nearly uniform temperature throughout, whereas the ceramic and oak floors are able to sustain a higher temperature beneath the point at which the hot melt is dripping onto the surface. In general, the spread rate is controlled by the viscosity at the outer edges of the melt pool. The spread rate over steel is therefore fastest, especially for a thin floor that rapidly increases in temperature. The low thermal inertia of oak results in rapid changes in surface temperature, which traps the heat close to the interface between the floor and the melt and maintains a high temperature and low viscosity in the center of the melt pool. The ceramic floor transports heat more readily and may develop a hot spot underneath. The material properties of ceramic lie between those of oak and steel, but although the spread rate over a steel floor is always faster than over ceramic, the spread rate over oak may not always be slower.

  Abstract
  The effects of the thermal properties of three flooring materials on the spread rate of polymer melt over the surface were studied using a model based on the Particle Finite [...]

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• Modeling thermoplastic melt spread over different flooring materials

  K. Butler, E. Oñate, R. R. Rossi, J. Marti, S. Idelsohn

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2017).

  
  

  Abstract

  The effects of the thermal properties of three flooring materials on the spread rate of polymer melt over the surface were studied using a model based on the Particle Finite Element Method (PFEM). The high thermal conductivity of steel keeps the steel floor at a nearly uniform temperature throughout, whereas the ceramic and oak floors are able to sustain a higher temperature beneath the point at which the hot melt is dripping onto the surface. In general, the spread rate is controlled by the viscosity at the outer edges of the melt pool. The spread rate over steel is therefore fastest, especially for a thin floor that rapidly increases in temperature. The low thermal inertia of oak results in rapid changes in surface temperature, which traps the heat close to the interface between the floor and the melt and maintains a high temperature and low viscosity in the center of the melt pool. The ceramic floor transports heat more readily and may develop a hot spot underneath. The material properties of ceramic lie between those of oak and steel, but although the spread rate over a steel floor is always faster than over ceramic, the spread rate over oak may not always be slower.

  Abstract
  The effects of the thermal properties of three flooring materials on the spread rate of polymer melt over the surface were studied using a model based on the Particle Finite [...]

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• Desarrollo de una Herramienta de Procesamiento de Imágenes Médicas en MATLAB y su Integración en Medical GiD

  G. Gavidia, M. Cerrolaza, E. Oñate, E. Soudah, J. Ronda

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2017).

  
  

  Abstract

  El rápido avance de las tecnologías de adquisición de imágenes médicas ha hecho necesario el desarrollo de diversas aplicaciones en el área de la biomedicina. Por un lado, el trabajo que los médicos desarrollan en cuanto al análisis de las imágenes, es arduo y sujeto a errores, por lo que se hace necesaria la implementación de algoritmos de procesamiento que automaticen esta tarea y sirvan de soporte a los profesionales de la salud para realizar un diagnóstico fiable. Por otro lado, los biomédicos dedicados al modelado y simulación del cuerpo humano y el diseño de prótesis e implantes para tratamiento médico, requieren de modelos geométricos que consideren la complejidad característica de las estructuras anatómicas del cuerpo humano y les permita realizar un modelado discreto más preciso. Es por esto, que la comunidad de biomédicos, particularmente el área de analistas de imágenes médicas, hoy en día, dedican sus esfuerzos a extraer con ayuda del ordenador, información clínica, cualitativa y cuantitativa de las estructuras del cuerpo humano: tejidos blandos, duros, fluidos y sus patologías a partir del procesamiento de imágenes médicas de diversas modalidades: Tomografía Computarizada, Resonancia Magnética, Medicina Nuclear, entre otras.

  Abstract
  El rápido avance de las tecnologías de adquisición de imágenes médicas ha hecho necesario el desarrollo de diversas aplicaciones en el área [...]

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• Interfase GiD per a la generació paramètrica de geometries trenades per a l’apantallament de cables coaxials

  R. Méndez, R. Isanta, R. Otín, O. Fruitos

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2017).

  
  

  Abstract

  En aquest informe tècnic es presenta un programa que genera automàticament geometries trenades per a l’apantallament (shielding) de cables coaxials i que s’integra en l’entorn GiD. L’objectiu general d’aquest treball és desenvolupar una eina numèrica capaç de generar la geometria inicial de la simulació electromagnètica. Aquesta simulació electromagnètica té com a propòsit calcular la transferència d’impedància d’aquests trenats d’apantallament. La transferència d’impedància és una magnitud que caracteritza l’eficàcia d’aquest apantallament. Una baixa transferència indica un bon apantallament. El desenvolupament d’aquesta eina numèrica ajudarà a optimitzar el disseny de trenats (com menys material, més bon apantallament) i per arribar a comprendre bé la física del problema. A més a més, l’avantatge d’emprar una eina numèrica basada en el mètode dels elements finits en lloc de càlculs analítics és que se serà capaç d’aplicar per materials i geometries generals i al mateix temps complexes. L’eina que es vol costumitzar es diu ERMES (Electric Field Regularized Maxwell Equations with Singularities), i és un codi d’elements finits que empra GiD [1] com a pre i post processador. Fins al moment de la elaboració del present informe, s’està desenvolupant l’eina de generació de geometria per separat d’ERMES [4].

  Abstract
  En aquest informe tècnic es presenta un programa que genera automàticament geometries trenades per a l’apantallament (shielding) de cables coaxials i que [...]

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• Implementation of an Automated Benchmarking module for Kratos

  F. Mossaiby

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2008).

  
  

  Abstract

  The size and complexity of software projects have increased considerably in the last years. Huge projects may involve hundreds or thousands of people working simultaneously on the same code base. This has increased the importance of Revision Control Systems. Revision Control Systems keep track of all changes done in a source code. More sophisticated systems may also be able to keep track of branches in the code. Without such tools, the development of huge softwares, e.g. operating systems would not be possible. The Revision Control Systems help, among other things, minimizing the cost of source code maintenance and management. This can be very critical for large projects. Also, these systems help finding out bugs introduced in the code base while adding new features or fixing other bugs. For example, consider a scenario of adding a new feature in a program. This may involve changing the behavior of a previously used function. This may impact other parts of the code base which use it. The Kratos project [1] at CIMNE is an open source Multi-physics software based on the Finite Element Method. Kratos due to its multi-disciplinary nature contains a large collection of numerical algorithms, Finite Elements, etc. It is being actively used and developed in CIMNE and also worldwide. Kratos currently uses CVS (Concurrent Versions System) [2] as its Revision Control System. Users can fetch the most current version of Kratos via CVS, and use / modify / improve it. Also, users can commit modifications / improvements back to the code base, without much effort. While this open architecture of Kratos has great advantages, it may cause some problems. For a simple example, consider a user commits a change which affects a wide range of users. As the users regularly update their local code base to get the newest updates, the committed change propagates, and as a result, compilation of a previously working program may fail or results of a program may change. In former case, the existence of a conflict can easy be detected, but in the latter, it may be hidden for a long time, and lead to confusing results. Although there is no reliable way to prevent such conflicts, and also it is very hard to distinguish them from other improvements done in the code base which may also lead to change of the results, a practical technique is needed to minimize the impact of changes by a user on the others. There are a number of test examples in the Kratos, which can be regarded as a representative of the code base functionality. A major change in the behavior of these test examples may indicate a possible conflict, and needs to be reviewed carefully. The steady and careful checking process of the test examples is almost impossible for developers and users of Kratos, and needs to be automated. This has been the inspiration of development of an Automated Benchmarking module. During the nightly builds of Kratos, which will be done on the upcoming Kratos server, this module automatically runs all test examples and verifies the results against a reference data set. It will send an email containing the status of each test example to a list of recipients. This can be useful in several ways. First, it will be clear when a conflict has occurred. This will help greatly to find the user committed the changes, ask him / her to correct / undo it. Also, it will let other users to be aware of a conflict in the latest code base, and avoid updating their own local code base, before it has been corrected. This can save them a lot of time and effort.

  Abstract
  The size and complexity of software projects have increased considerably in the last years. Huge projects may involve hundreds or thousands of people working simultaneously [...]

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• CIMNE Verification of the validation analysis of Xfinas elements database

  E. Oñate, A. Larese

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2009).

  
  

  Abstract

  In order to validate the Xfinas code a very comprehensive series of test examples were solved by Prof Ki-Du Kim and his co-workers. A collection of the more representative benchmarks were chosen at CIMNE for testing the good behavior of every element implemented in the software. The aim of the validation work carried out at CIMNE has been to asses the accuracy of the Xfinas program. This was done studying the whole validation process carried out by Prof Ki-Du Kim’s team in detail. For this purpose we have chosen at CIMNE randomly the different benchmarks to be reproduced between those of the validation manual (VM from now on). In every example we checked the agreement of the results with the Xfinas validation data.

  Abstract
  In order to validate the Xfinas code a very comprehensive series of test examples were solved by Prof Ki-Du Kim and his co-workers. A collection of the more representative [...]

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• Reflexiones sobre el tránsito de la idea al producto en el entorno de la escuela de ingenieros de caminos de Barcelona

  E. Oñate

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2017).

  
  

  Abstract

  Some reflections are presented on the cycle that ideas go through from when they arise in a university environment until they become an industrial product. These reflections are concreted in the context of the School of Civil Engineers of BarcelonaTech. Some success examples in the implementation of the so-called Cycle of Ideas are presented.

  Abstract
  Some reflections are presented on the cycle that ideas go through from when they arise in a university environment until they become an industrial product. These reflections [...]

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• Cálculo de un depósito de hidrógeno

  M. Coma, A. Ferriz, O. Fruitos, X. Martinez

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2017).

  
  

  Abstract

  This report presents the results of four models obtained with the version 1.0 of FEMCOM. In the first two cases hexahedral elements have been used. In the first case the geometry provided by ACCIONA is studied. The second study case is a variation of the previous model, also with hexahedral elements, adding reinforcement in the dome. The last two cases are simulations with shell elements using the thickness data provided by ACCIONA and increased thicknesses. The aluminum alloy liner 4.2 mm thick was incorporated, which was not included in the simulations with shell elements sent to ACCIONA in the report [3]. It has been thought to use hexahedral elements in order to obtain more accurate results considering the complexity of the dome geometry.

  Abstract
  This report presents the results of four models obtained with the version 1.0 of FEMCOM. In the first two cases hexahedral elements have been used. In the first case the geometry [...]

  • 0
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• Simulador de voladura en macizos rocosos

  C. Labra, F. Zárate

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2017).

  
  

  Abstract

  In recent years, the discrete element method (DEM) has proved to be a very useful tool for the development of numerical simulations in problems of geomechanics and dynamics of particulate material. The discretization of the solid materials through a packing of particles makes feasible the modeling of strong discontinuities, such as those generated by the fracture and other related phenomena, which present an intrinsic difficulty for continuous methods, such as the finite element method (FEM). It is for this reason that the use of this class of methods has an increasing importance in the study of the phenomena that appear in the processes of excavation and earthmoving. In the present work, DEM is used to simulate the behavior of the terrain during the excavation or removal of material by controlled explosions, for which the method will be used with cylindrical (2D) and spherical (3D) particles. The medium is represented as a cohesive assembly of rigid particles. The breaking of these cohesive bonds between particles, modeled with a law at the microscopic level, will simulate the fracture of the material.

  Abstract
  In recent years, the discrete element method (DEM) has proved to be a very useful tool for the development of numerical simulations in problems of geomechanics and dynamics [...]

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• Cálculo de láminas por métodos analíticos

  M. Tort, E. Oñate

  Technical Reports of the International Centre for Numerical Methods in Engineering (CIMNE) (2009).

  
  

  Abstract

  The forms of revolution generated by shell structures are the simplest of classical art. Thus, the main motivation of this paper is present the basic tools for understanding shell behavior and the reader can design it without any problems. The text will focus on analyzing the two most common shells. First the dome and second cylindrical wall. Having analyzed the two types we will look the union between these two types and see the ring edge necessary in many cases.

  Abstract
  The forms of revolution generated by shell structures are the simplest of classical art. Thus, the main motivation of this paper is present the basic tools for understanding [...]

  • 490
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Online first articles (not assigned to a volume)