http://hdl.handle.net/2117/3511 2013-05-23T13:09:23Z 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/2117/18261 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/2117/17267 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/2117/9698 Title: Analysis of masonry structures by funicular networks Authors: Andreu Torras, Antoni; Gil Espert, Lluís; Roca Fabregat, Pedro Abstract: A numerical approach for the ultimate analysis of large masonry structures composed of multiple linear members is presented. The approach is based on the use of computer-simulated cable nets representing the equilibrium lines (or load paths) that describe the equilibrium condition of structures. Based on this description, limit analysis is applied according to the static approach. Cable net solutions complying with the limit theorems of plasticity – in particular the safe (or lower-bound) and the uniqueness theorems – are generated by means of convenient optimisation techniques. An efficient cable element is adopted with explicit analytical expressions available for the description of the deformed shape in equilibrium and the tangent stiffness matrix. This type of cable element enables the computation of very large cable nets, including a large number of individual cables, with high computational efficiency. The calculation procedure is applied to complex spatial structures and the ability of the technique to deal with such systems is illustrated by an example involving a practical assessment of a real three-dimensional masonry structure. 2010-10-14T14:34:11Z http://hdl.handle.net/2117/8444 Title: A contact domain method for large deformation frictional contact problems. Part 1: Theoretical basis Authors: Oliver Olivella, Xavier; Hartmann, S; Cante Terán, Juan Carlos; Weyler Pérez, Rafael; Hernández Ortega, Joaquín Alberto Abstract: In the first part of this work, the theoretical basis of a frictional contact domain method for two-dimensional large deformation problems is presented. Most of the existing contact formulations impose the contact constraints on the boundary of one of the contacting bodies, which necessitates the projection of certain quantities from one contacting surface onto the other. In this work, the contact constraints are formulated on a so-called contact domain, which has the same dimension as the contacting bodies. This contact domain can be interpreted as a fictive intermediate region connecting the potential contact surfaces of the deformable bodies. The introduced contact domain is subdivided into a non-overlapping set of patches and is endowed with a displacement field, interpolated from the displacements at the contact surfaces. This leads to a contact formulation that is based on dimensionless, strain-like measures for the normal and tangential gaps and that exactly passes the contact patch test. In addition, the contact constraints are enforced using a stabilized Lagrange multiplier formulation based on an interior penalty method (Nitsche method). This allows the condensation of the introduced Lagrange multipliers and leads to a purely displacement driven problem. An active set strategy, based on the concept of effective gaps as entities suitable for smooth extrapolation, is used for determining the active normal stick and slip patches of the contact domain. Description: Continua a l'article "A contact domain method for large deformation frictional contact problems. Part 2: Numerical aspects" publicat a la revista "Computer methods in applied mechanics and engineering", 2009, vol. 198, p. 2607-2631. 2010-07-28T11:32:43Z http://hdl.handle.net/2117/8441 Title: A contact domain method for large deformation frictional contact problems. Part 2: Numerical aspects Authors: Hartmann, S.; Oliver Olivella, Xavier; Weyler Pérez, Rafael; Cante Terán, Juan Carlos; Hernández Ortega, Joaquín Alberto Abstract: This second part of the work describes the numerical aspects of the developed contact domain method for large deformation frictional contact problems. The theoretical basis of this contact method is detailed in the first part of this work. Starting from this, the present contribution focuses on describing important algorithmic details that go along with the finite element implementation for two-dimensional problems. Important aspects are the construction of the contact domain mesh, via a constraint Delaunay triangulation, the linearization of the discretized contact contributions and some important technical aspects about the extrapolation procedure used for the predictive active set strategy. Finally a set of numerical examples is presented to demonstrate the performance of the developed contact strategy. Demanding static and dynamic contact problems in the context of large deformations, including frictional effects as well as self contact, show the wide applicability and the robustness of the proposed method. Description: Continuació de l'article "A contact domain method for large deformation frictional contact problems. Part 1: Theoretical basis" publicat a la revista Computer Methods in Applied Mechanics and Engineering, Vol. 198, #33-36, July 2009, p. 2591-2606 2010-07-28T11:16:35Z http://hdl.handle.net/2117/6480 Title: Estudio de la interfaz hormigón-epoxi-frp de un ensayo de doble cortante por medio de la teoría de mezclas serie/paralelo Authors: Molina Herrera, Maritzabel; Cruz Solís, Juan José; Oller Martínez, Sergio Horacio; Barbat Barbat, Horia Alejandro; Gil Espert, Lluís Abstract: El uso de los compuestos para la rehabilitación y la reparación de estructuras de hormigón y de acero se ha ido imcrementando en las ultimas décadas. Frente a la necesidad de entender de una forma más apropiada el comportamiento de las estructuras reforzadas, la simulación numérica de los materiales compuestos ha surgido como una herramienta; sin embargo, es un campo que aún está en desarrollo. En este trabajo se desarrolla la teoría de mezclas serie/paralelo como una alternativa eficiente para el análisis de estructuras reforzados con fibras largas (FRP) y se estudia con detalle el comportamiento de la interfaz hormigón-adhesivo-FRP. Utilizando el programa de elementos finitos no lineal PLCDYN, se hace una simulación tridimensional de un ensayo de doble cortante y se compara con los resultados obtenidos en el laboratorio. Se han podido evidenciar las ventajas de esta teoría como herramienta para el análisis numérico de los materiales compuestos. 2010-02-25T15:50:35Z