Browsing by Subject "Granular materials"

Now showing items 1-20 of 20

    • A continuum–discrete multiscale methodology using machine learning for thermal analysis of granular media 

      Nazareth López, Rafael; Gimenez, Juan Marcelo; Oñate Ibáñez de Navarra, Eugenio; Franci, Alessandro (Elsevier, 2024-04)
      Article
      Open Access
      This work presents a data-driven continuum–discrete multiscale methodology to simulate heat transfer through granular materials. The two scales are hierarchically coupled, where the effective thermal conductivity tensor ...

    • A rockfill triaxial cell with suction control 

      Chavez, C.; Romero Morales, Enrique Edgar; Alonso Pérez de Agreda, Eduardo (2009-05)
      Article
      Restricted access - publisher's policy
      This paper describes the development of a new triaxial cell specifically built to test coarse granular material under partially saturated conditions. The partial saturation is achieved by imposing a total suction that is ...

    • An experimental study of ultrasonic vibration and the penetration of granular material 

      Firstbrook, David; Worrall, Kevin; Timoney, Ryan; Suñol Galofre, Francesc Xavier; Gao, Yang; Harkness, Patrick (2017-02-01)
      Article
      Open Access
      This work investigates the potential use of direct ultrasonic vibration as an aid to penetration of granular material. Compared with non-ultrasonic penetration, required forces have been observed to reduce by an order of ...

    • Breakage of an artificial crushable material under loading 

      Casini, Francesca; Viggiani, Giulia M.B.; Springman, Sarah Marcella (2013-10)
      Article
      Restricted access - publisher's policy
      The mechanical behaviour of granular materials depends on their grading. Crushing of particles under compression or shear modifies the grain size distribution, with a tendency for the percentage of fine material to increase. ...

    • Continuum modelling using the Discrete Element Method. Theory and implementation in an object-oriented software platform 

      Santasusana Isach, Miquel (Universitat Politècnica de Catalunya / Centre Internacional de Mètodes Numèrics en Enginyeria, 2012-07-28)
      Minor thesis
      Open Access
      [ANGLÈS] The Discrete Element Method is a relatively new technique that has nowadays and intense research in the field of numerical methods. In its first conception, the method was designed for simulations of dynamic ...

    • Elastoplastic simulation of contacts among particles in granular materials 

      Riera Colom, María Dolores; Prado Pozuelo, José Manuel (European Powder Metallurgy Association, 2003)
      Conference report
      Open Access
      The mechanisms governing the densification of powdered materials under compaction are highly dependent on the deformation and the state of stress in the contact among particles. Therefore, a micromechanical model can be ...

    • Estudio experimental del llenado de moldes pulvimetalúrgicos 

      Istúriz Mota, Álvaro; Riera Colom, María Dolores; Prado Pozuelo, José Manuel (2005-10)
      Article
      Open Access
      En el proceso de conformado pulvimetalúrgico, la consolidación del polvo se inicia con el llenado del molde en el que se fabricará la preforma porosa, el cuál está caracterizado por la distribución de densidades del polvo ...

    • Experimental and theoretical study of the capillary effect on the mechanical behaviour of granular media 

      Moure i Foraster, Carla (Universitat Politècnica de Catalunya, 2012-06-29)
      Minor thesis
      Open Access
      [ANGLÈS] Effective stress in unsaturated soils has never been physically or mathematically defined. It is still the topic in large discussions and debates in the soil mechanics community. We therefore tried to obtain a ...

    • Experimental study of mass flow and apparent density in powder metallurgy die filling 

      Riera Colom, María Dolores; Istúriz, Álvaro; Prado Pozuelo, José Manuel (European Powder Metallurgy, 2005)
      Conference report
      Open Access
      Die filling is the first step in the process of powder compaction. The density distribution after die filling on the powder properties and the method of filling. In this work the authors study the effects of powders ...

    • Flow regime analyses during the filling stage in powder metallurgy processes: experimental study and numerical modelling 

      Cante Terán, Juan Carlos; Riera Colom, María Dolores; Oliver Olivella, Xavier; Prado Pozuelo, José Manuel (2011-01)
      Article
      Open Access
      Experimental and numerical studies of powder flow during the die filling stage in powder metallurgy cold compaction processes are presented. An experimental setting consisting of a horizontal pneumatically activated ...

    • Imaging and discrete modelling of sand shape 

      Rorato, Riccardo (Universitat Politècnica de Catalunya, 2019-11-08)
      Doctoral thesis
      Open Access
      The shape of particles is known to play an important role in soil behaviour, with significant effects of engineering responses. Investigating how the shape of particles can be measured and quantified is therefore considered ...

    • Irreversible behaviour of crushable sands: a DEM study 

      Gens Solé, Antonio; Ciantia, Matteo Oryem; Arroyo Alvarez de Toledo, Marcos (2017)
      Conference report
      Restricted access - publisher's policy
      The irreversible behaviour of crushable sands is investigated by means of a Discrete Element Method (DEM) analogue. The calculations have been performed using a recently developed procedure to simulate particle crushing ...

    • Micromechanical inspection of incremental behaviour of crushable soils 

      Ciantia, Matteo Oryem; Arroyo Alvarez de Toledo, Marcos; O'Sullivan, Catherine; Gens Solé, Antonio (Springer, 2019-10)
      Article
      Open Access
      In granular soils grain crushing reduces dilatancy and stress obliquity enhances crushability. These are well-supported specimen-scale experimental observations. In principle, those observations should reflect some peculiar ...

    • A micromechanical study of the Standard Penetration Test 

      Zhang, Ningning (Universitat Politècnica de Catalunya, 2020-01-20)
      Doctoral thesis
      Open Access
      This thesis explores the potential of models based on the discrete element method (DEM) to study dynamic probing of granular materials, considering realistic particle-scale properties. The virtual calibration chamber ...

    • Modelización y simulación de la etapa de compactación en PM 

      Riera Colom, María Dolores; Prado Pozuelo, José Manuel (2006-11)
      Article
      Open Access
      La industria pulvimetalúrgica está interesada en extender las aplicaciones y mejorar la calidad de sus productos. Para ello, necesita un conocimiento detallado de sus procesos que permita su control. La representación del ...

    • Modelling of the plasticity in cold compaction of metal powders 

      Riera Colom, María Dolores; Prado Pozuelo, José Manuel (Universidad Carlos III de Madrid (UC3M), 2001)
      Conference report
      Open Access
      Powder Metallurgical Industry is very interested in spreading its applications and improve the quality of the PM products. Therefore, a detailed knowledge of their processes, in order to control them, is necessary. Many ...

    • On the incremental behaviour of sands at high stresses 

      Ciantia, Matteo Oryem; Arroyo Alvarez de Toledo, Marcos; Gens Solé, Antonio (International Society for Soil Mechanics and Geotechnical Engineering (ISSMGE), 2019)
      Conference report
      Open Access
      The mechanical behaviour of granular materials is characterized by strong non-linearity and irreversibility. In particular, particle breakage will induce additional plastic deformations beyond those which might be expected ...

    • Particle finite element method applied to granular material flow 

      Cante Terán, Juan Carlos; Oliver Olivella, Xavier; Weyler Pérez, Rafael; Cafiero, Mailhyn E.; Dávalos Chargoy, César Emilio (CIMNE (Centro Internacional de Métodos Numéricos en Ingeniería), 2009-11-25)
      Conference report
      Open Access
      A numerical model, based on a rate-dependent constitutive model, via a flow formulation, and in the framework of the particle finite element method (PFEM) is proposed. It is settled on the assumption that the powder can ...

    • Simulation of the compaction process of a two-level powder metallurgical part 

      Bejarano, C; Riera Colom, María Dolores; Prado Pozuelo, José Manuel (Universidad Carlos III de Madrid (UC3M), 2001)
      Conference report
      Open Access
      In this work, a Plasticity model for granular materials, based on the Drucker-Prager/CAP model, is applied to represent the behaviour of the metallic powders during their cold die compaction. The elastic deformation has ...

    • Steady state of solid-grain interfaces during simulated CPT 

      Butlanska, Joanna; Arroyo Alvarez de Toledo, Marcos; Gens Solé, Antonio (2013)
      Article
      Restricted access - publisher's policy
      It has recently been shown (Arroyo et al. [1]) that 3D DEM models are able to reproduce with reasonable accuracy the macroscopic response of CPT performed in calibration chambers filled with sand. However, the cost of ...