ConstitutiveLaws

From Yade

This page should grow to give overview of all constitutive laws (a.k.a. InteractionSolvers) and interaction-related classes in Yade. The purpose is twofold:

  1. Names of respective classes do not say much and it seems that lot of code is duplicated; should improve orientation in material models available
  2. Have overview of migration to ConstitutiveLawDispatcher and ConstitutiveLaw (moving the interaction loop away from the law code), removal of persistentInteraction and obsolete code.

Please add what you know something about.

Constitutive laws

Class description interactionGeometry interactionPhysics used by and where
ElasticContactLaw (the traditional Cundall's elastic-plastic law) This law has three parameters : tangential stiffness, normal stiffness, and friction coefficient - it modelises dry contacts (no tensile force allowed). SpheresContactGeometry ElasticContactInteraction TriaxialTest (Bruno Chareyre)
CohesiveFrictionalContactLaw A versatile elastic-plastic contact law, with shear/normal/twisting/rolling stiffnesses, normal/shear strength (twisting/rolling strength could be added easily, for now they are infinite), shear/twisting creep SpheresContactGeometry CohesiveFrictionalInteraction CohesiveTriaxialTest (Bruno Chareyre/Cosurgi)
Concrete particle model (Cpm) (stands for BReakableFrictionalCohesive) material model developed for concrete. It has damage, plasticity (friction), planned is visco-damage and visco-plasticity. The code unfortunately cannot be disclosed by contract, but algorithms will be published some day. SpheresContactGeometry BrefcomContact BrefcomTestGen, scripts (eudoxos)
ef2_Spheres_NormalShear_ElasticFrictionalLaw Proof-of-concept for ConstitutiveLawDispatcher. Cohesive type of interaction; has elasticity in both normal and shear directions. SpheresContactGeometry NormalShearInteraction scripts/constitutive-law.py (eudoxos)
ElasticContactLaw2 like ElasticContactLaw, but using geometry algorithms in SpheresContactGeometry instead of computing that in-place; demonstrative only SpheresContactGeometry ElasticContactInteraction (eudoxos)
ElasticCohesiveLaw (deprecated) inherited from SDEC, not used anywhere except SDECLinkedSpheres SDECLinkGeometry SDECLinkPhysics to be removed (relies on persistentInteractions)?
Spheres_Viscoelastic_SimpleViscoelasticContactLaw Linear spring−dashpot contact model SpheresContactGeometry ViscoelasticInteraction (sega) for dynamic simulation
RockJointLaw Inelastic normal behaviour (kn_unload # kn_load); transfert of an elastic-plastic moment; no cohesion or tensile limit SpheresContactGeometry RockJointPhys J. Duriez for simulations of "SimpleShear" Preprocessor (a simple shear box for studying rock joints)
CapillaryLaw Model of capillary force between spheres (as explained in REF) SpheresContactGeometry CapillaryPhys L. Scholtes for simulation of unsaturated granular materials (e.g. TriaxialTestWater)
add your stuff here, please! ... ... ...

InteractionPhysicsEngineUnits

Class description physicalParameters interactionPhysics remarks
BrefcomMakeContact from the Brefcom* family; elastic, damage, plasticity, viscosity properties BrefcomPhysParams (BodyMacro + per-body damage and plasticity accounting) BrefcomContact (eudoxos)
SimpleElasticRelationships ... ... ...
SimpleViscoelasticRelationships From viscoelastic parameters of the pair bodies provides viscoelastic parameters of their interaction by the rule of consecutive connection. SimpleViscoelasticBodyParameters ViscoelasticInteraction (sega)
RockJointLawRelationships Computes all the attributes of "RockJointPhys" used for application of RockJointLaw CohesiveFrictionalBodyParameters RockJointPhys J. Duriez for SimpleShear

InteractionGeometry

Class description
SpheresContactGeometry used almost everywhere in the DEM code, even for sphere-box contacts.
SDECLinkGeometry duplicated SpheresContactGeometry. (Should be removed)
... .....

InteractionPhysics

Class description
NormalInteraction abstract class that has only normal stiffness and force
NormalShearInteraction abstract class with normal and shear stiffnesses
BrefcomContact normal and shear physics with additional parameters for non-elastic domain.
ViscoelasticInteraction elastic contact with additional parameters for normal and shear dashpot.
RockJointPhys
...