How to model orthotropic materials by the Discrete Element Method (DEM): random sphere packing or regular cubic arrangement?
TypeArticles dans des revues avec comité de lecture
The discrete element method (DEM) is used for continuous material modeling. The method is based on discretizing mass material into small elements, usually spheres, which are linked to their neighbours through bonds. If DEM has shown today its ability to model isotropic materials, it is not yet the case of anisotropic media. This study highlights the obstacles encountered when modeling orthotropic materials. In the present application, the elements used are spheres and bonds are Euler-Bernoulli beams developed by André et Al. . Two different modeling approaches are considered: cubic regular arrangements, where discrete elements are placed on a regular Cartesian lattice, and random sphere packed arrangements, where elements are randomly packed. As the second approach is by definition favoring the domain’s isotropy, a new method to affect orientation-dependent Young’s modulus of bonds is proposed to create orthotropy. Domains created by both approaches are loaded in compression in-axis (along the material orthotropic directions) and off-axis to determine their effective Young’s modulus according to the loading direction. Results are compared to the Hankinson model which is especially used to represent high orthotropic behavior such as encountered in wood or synthetic fiber materials. For this class of materials, it is shown that, contrary to cubic regular arrangements, the random sphere packed arrangements exhibit difficulties to reach highly orthotropic behavior (in-axis tests). Conversely, this last arrangements display results closer to continuous orthotropic material during off-axis tests.
Files in this item
Showing items related by title, author, creator and subject.
POT, Guillaume; DENAUD, Louis; COLLET, Robert; GIRARDON, Stéphane; COTTIN, Fabrice (FPInnovations, 2015)Laminated veneer lumber (LVL) is a high-performance engineered wood product made of several wood veneers bound together mostly in grain direction. Veneers are obtained thanks to peeling process. This cutting process induces ...
Modelling the effects of wood cambial age on the effective modulus of elasticity of poplar laminated veneer lumber GIRARDON, Stéphane; DENAUD, Louis; POT, Guillaume; RAHAYU, Istie (Springer, 2016)Key messageA modelling method is proposed to highlight the effect of cambial age on the effective modulus of elasticity of laminated veneer lumber (LVL) according to bending direction and veneer thickness. This approach ...
PFEIFFER, Renaud; COLLET, Robert; DENAUD, Louis; FROMENTIN, Guillaume; LORONG, Philippe (2013)During the primary transformation of wood, logs are faced with slabber heads. Chips produced are raw materials for pulp paper and particleboard industries. Efficiency of these industries is partly due to particle size ...
Mechanical behaviour of pre-stressed spruce timber–timber 2.5-mm-step grooved connections under shearing tests GIRARDON, Stéphane; BOCQUET, Jean-François (Springer Nature, 2017)A smart shear connection system was tested in order to be used in manufactured elements of a lattice of wooden slats and a cross offset. This type of floor element can present advantages both in terms of weight and suitable ...
Lathe check development and properties: effect of log soaking temperature, compression rate, cutting radius and cutting speed during peeling process of European beech (Fagus sylvatica L.) veneer ROHUMAA, Anti; VIGUIER, Joffrey; GIRARDON, Stéphane; KREBS, Michael; DENAUD, Louis (Springer, 2018)The depth of lathe checks and integrity of veneer have been shown to be critical factors affecting the bonding process but also affecting the mechanical properties of veneer-based products. This study shows how beech (Fagus ...