http://hdl.handle.net/2117/4002 2013-05-22T00:00:44Z http://hdl.handle.net/2117/18871 Title: Self-assessment exercises in continuum mechanics with autonomous learning Authors: Marcé Nogué, Jordi; Gil Espert, Lluís; Pérez Martínez, Marco Antonio; Sánchez Romero, Montserrat 2013-04-18T13:59:09Z http://hdl.handle.net/2117/18813 Title: Adaptive finite element simulation of incompressible flows by hybrid continuous-discontinuous Galerkin formulations Authors: Badia Rodríguez, Santiago I.; Baiges Aznar, Joan Abstract: In this work we design hybrid continuous-discontinuous finite element spaces that permit discontinuities on non-matching element interfaces of non-conforming meshes. Then, we develop an equal-order stabilized finite element formulation for incompressible flows over these hybrid spaces, which combines the element interior stabilization of SUPGtype continuous Galerkin formulations and the jump stabilization of discontinuous Galerkin formulations. Optimal stability and convergence results are obtained. For the adaptive setting, we use an standard error estimator and marking strategy. Numerical experiments show the optimal accuracy of the hybrid algorithm both for uniformly and adaptively refined non-conforming meshes. The outcome of this work is a finite element formulation that can naturally be used on nonconforming meshes, as discontinuous Galerkin formulations, while keeping the much lower CPU cost of continuous Galerkin formulations. 2013-04-16T12:27:53Z http://hdl.handle.net/2117/18804 Title: Un caso práctico de meta-evaluación docente: el manual de evaluación de la Universidad Politécnica de Cataluña Authors: García-Berro Montilla, Enrique; de la Vega, Ricardo; Gemma, Amblàs; Martínez, Erica; Laura, Campeny; Bugeda Castelltort, Gabriel; Roca, Santiago Abstract: La Universidad Politécnica de Cataluña ha sido pionera en la introducción de un modelo de eva- luación docente plenamente adaptado a las exigencias del Espacio Europeo de Enseñanza Supe- rior. Además, su sistema de evaluación de la actividad docente del profesorado ha sido homologa- do por la AQU y ANECA. Dicho modelo de evaluación docente se basa en las más recientes di- rectrices europeas y tiene como fundamento diversos indicadores indirectos. Este modelo se ha em- pleado para evaluar la docencia del profesorado en cinco convocatorias. Durante este periodo de tiempo se ha acumulado una información valiosísima que permite obtener datos agregados no só- lo de la calidad de los docentes sino, también, de diversas características inherentes al proceso de evaluación, así como de la bondad de los indicadores empleados. En este artículo se presentan es- tos datos y se muestra un conjunto de datos agregados que permiten estimar la bondad y fiabilidad del proceso de evaluación, así como su aceptación por el profesorado evaluado. 2013-04-15T15:46:10Z http://hdl.handle.net/2117/18261 Title: The structural performance of arches made of few vossoirs with dry-joints Authors: Bernat Masó, Ernest; Gil Espert, Lluís; Marcé Nogué, Jordi 2013-03-13T14:24:00Z 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. 2013-03-05T17:20:17Z http://hdl.handle.net/2117/17613 Title: Comportamiento sismico de los edificios de Lorca Authors: Carreño Tibaduiza, Martha Liliana; Lantada Zarzosa, Maria de Las Nieves; Irizarry, Janira; Valcarcel, Jairo Andrés; Barbat Barbat, Horia Alejandro; Goula Suriñach, Xavier Abstract: Después de ocurrido el terremoto de Lorca, el 11 de mayo de 2011, el Institut Geològic de Catalunya (IGC), la Universidad Politécnica de Cataluña (UPC) y la Asociación Española de Ingeniería Sísmica (AEIS) organizaron, junto con las asociaciones de ingeniería sísmica francesa (AFPS) y portuguesa (SPES), una visita técnica con el objeto de realizar observaciones que permitieran calibrar, verificar y validar los métodos utilizados en las evaluaciones de riesgo sísmico en zonas urbanas. Este artículo resume los aspectos más destacados en cuanto a la observación de la vulnerabilidad de edificios de vivienda, así como de edificios de especial importancia como son hospitales y escuelas. After the earthquake of Lorca, May 11, 2011, the Geological Institute of Catalonia (IGC), the Technical University of Catalonia (UPC) and the Spanish Association for Earthquake Engineering (AEIS) organized a technical visit in order to compile information that allow to calibrate, to verify and to validate the methods used in seismic risk assessments in urban areas. This article summarizes the highlights regarding the vulnerability of residential buildings and buildings of special importance such as hospitals and schools. 2013-02-08T13:59:10Z http://hdl.handle.net/2117/17285 Title: Unconditionally stable operator splitting algorithms for the incompressible magnetohydrodynamics (MHD) system discretized by a stabilized finite element formulation based on projections Authors: Badia Rodríguez, Santiago I.; Planas Badenas, Ramon; Gutierrez Santacreu, Juan Vicente Abstract: In this article we propose different splitting procedures for the transient incompressible MHD system that are unconditionally stable. We consider two levels of splitting, on one side we perform the segregation of the fluid pressure and magnetic pseudo-pressure from the vectorial fields computation. At the second level, the fluid velocity and induction fields are also decoupled. This way, we transform a fully coupled indefinite multi-physics system into a set of smaller definite ones, clearly reducing the CPU cost.With regard to the finite element approximation, we stick to an unconditionally convergent stabilized finite element formulation, since it introduces convection stabilization, allows to circumvent inf-sup conditions (clearly simplifying implementation issues) and is able to capture nonsmooth solutions of the magnetic sub-problem. However, residual-based finite element formulations are not suitable for segregation, since they lose the skew-symmetry of the off-diagonal blocks. Therefore, in this work we have proposed a novel term-by-term stabilization of the MHD system based on projections that is still unconditionally convergent. 2013-01-11T19:35:58Z http://hdl.handle.net/2117/17267 Title: Estudio numérico-experimental de la interfaz hormigón-epoxi-FRP para una estructura reforzada sometida a doble corte Authors: Molina, Maritzabel; Cruz Solís, Juan José; Oller Martínez, Sergio Horacio; Barbat Barbat, Horia Alejandro; Gil Espert, Lluís 2013-01-10T15:11:45Z http://hdl.handle.net/2117/17192 Title: Teaching engineering with autonomous learning tools: good practices in GRAPAU-RIMA Authors: Marcé Nogué, Jordi; Salán Ballesteros, Maria Núria; Aragoneses Aguado, Andrés; Bernat Masó, Ernest; Escrig Pérez, Christian; Otero Calviño, Beatriz; Rupérez de Gracia, Elisa; Illescas Fernandez, Silvia 2013-01-04T11:39:40Z http://hdl.handle.net/2117/17189 Title: An inverse approach for the mechanical characterisation of vascular tissues via a generalised rule of mixtures Authors: Bellomo, Facundo; Oller Martínez, Sergio Horacio; Nallim, Liz Abstract: Mechanical factors such as stresses and strains play a major role in the growth and remodelling of soft biological tissues. The main constituents of tissue undergo different processes reacting to mechanical stimulus. Thereby, the characterisation of growth and remodelling requires an accurate estimation of the stresses and strains of their main components. Many soft tissues can be considered as composite materials and can be analysed using an appropriate rule of mixtures. Particularly, arterial tissue can be modelled as an isotropic soft matrix reinforced with preferentially oriented collagen fibres. An inverse approach to obtain the mechanical characterisation of each main component is proposed in this work. The procedure is based on a rule of mixtures raised in a finite deformation framework and generalised to include kinematics and compatibility equations for serial–parallel behaviour. This methodology allows obtaining the stress–strain relationship of the components fitting experimental data. 2012-12-28T09:16:24Z http://hdl.handle.net/2117/17188 Title: On an unconditionally convergent stabilized finite element approximation of resistive magnetohydrodynamics Authors: Badia Rodríguez, Santiago I.; Codina, Ramon; Planas Badenas, Ramon Abstract: In this work, we propose a new stabilized finite element formulation for the approximation of the resistive magnetohydrodynamics equations. The novelty of this formulation is the fact that it always converges to the physical solution, even for singular ones. A detailed set of numerical experiments have been performed in order to validate our approach. 2012-12-28T07:41:49Z http://hdl.handle.net/2117/17130 Title: Finite point method to solve shallow water equations Authors: Ortega, Enrique; Oñate Ibáñez de Navarra, Eugenio; Idelsohn Barg, Sergio Rodolfo; Buachart, Chinapat Abstract: An adaptive Finite Point Method (FPM) for solving shallow water problems is presented. The numerical methodology we propose, which is based on weighted-least squares approximations on clouds of points, adopts an upwind-biased discretization for dealing with the convective terms in the governing equations. The viscous and source terms are discretized in a pointwise manner and the semi-discrete equations are integrated explicitly in time by means of a multi-stage scheme. Moreover, with the aim of exploiting meshless capabilities, an adaptive h-refinement technique is coupled to the described flow solver. The success of this approach in solving typical shallow water flows is illustrated by means of several numerical examples and special emphasis is placed on the adaptive technique performance. This has been assessed by carrying out a numerical simulation of the 26th December 2004 Indian Ocean tsunami with highly encouraging results. Overall, the adaptive FPM is presented as an accurate enough, cost-effective tool for solving practical shallow water problems. 2012-12-13T16:54:30Z 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. 2012-12-04T14:28:33Z http://hdl.handle.net/2117/16919 Title: On stabilized finite element methods based on the Scott-Zhang projector: circumventing the inf-sup condition for the Stokes problem Authors: Badia Rodríguez, Santiago I. Abstract: In this work we propose a stabilized nite element method that permits us to circumvent discrete inf-sup conditions, e.g. allowing equal order interpolation. The type of method we propose belongs to the family of symmetric stabilization techniques, which are based on the introduction of additional terms that penalize the di erence between some quantities, i.e. the pressure gradient in the Stokes problem, and their nite element projections. The key feature of the formulation we propose is the de nition of the projection to be used, a non-standard Scott-Zhang projector that is well-de ned for L1() functions. The resulting method has some appealing features: the projector is local and nested meshes or enriched spaces are not required. 2012-11-14T17:36:27Z http://hdl.handle.net/2117/16826 Title: Linear buckling analysis of perforated steel storage rack columns with the Finite Strip Method Authors: Casafont Ribera, Miguel; Pastor Artigues, María Magdalena; Bonada Bo, Jordi; Roure Fernández, Francisco; Peköz, Teoman Abstract: An investigation on the use of the Finite Strip Method (FSM) to calculate elastic buckling loads of perforated cold formed storage rack columns is presented. Nowadays, this calculation can be accurately performed by means of the Finite Element Method (FEM), because the effect of perforations can be explicitly considered in the analysis. However, the FSM is preferred in cold-formed steel design since it is implemented in much convenient and easy to use software. The problem with FSM is that holes cannot be easily modeled. In this paper, the concept of the reduced thickness of the perforated strip is applied to take into account their effect. A formulation is presented for the reduced thickness that has been calibrated with loads obtained in eigen-buckling FEM analyses. Its accuracy has been verified carrying out analyses on real rack columns with different end conditions 2012-10-31T18:35:08Z