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------------------------------------------------------------
revno: 2480
committer: bchareyre <bchareyre@dt-rv020>
branch nick: yade
timestamp: Wed 2010-10-13 17:04:25 +0200
message:
  - More documention in the 2 constitutive laws.
  - Some code cleaning and test redundancy fix in CohFrictPhys.cpp+CohesiveFrictionalContactLaw.cpp.
modified:
  pkg/dem/DataClass/IPhys/CohFrictPhys.cpp
  pkg/dem/Engine/GlobalEngine/CohesiveFrictionalContactLaw.cpp
  pkg/dem/Engine/GlobalEngine/CohesiveFrictionalContactLaw.hpp
  pkg/dem/Engine/GlobalEngine/ElasticContactLaw.hpp


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=== modified file 'pkg/dem/DataClass/IPhys/CohFrictPhys.cpp'
--- pkg/dem/DataClass/IPhys/CohFrictPhys.cpp	2010-05-24 15:50:25 +0000
+++ pkg/dem/DataClass/IPhys/CohFrictPhys.cpp	2010-10-13 15:04:25 +0000
@@ -10,10 +10,9 @@
 
 void CohFrictPhys::SetBreakingState()
 {	
-	if (fragile) {
-		cohesionBroken = true;
-		normalAdhesion = 0;
-		shearAdhesion = 0;}	
+	cohesionBroken = true;
+	normalAdhesion = 0;
+	shearAdhesion = 0;
 }
 
 CohFrictPhys::~CohFrictPhys()

=== modified file 'pkg/dem/Engine/GlobalEngine/CohesiveFrictionalContactLaw.cpp'
--- pkg/dem/Engine/GlobalEngine/CohesiveFrictionalContactLaw.cpp	2010-10-11 14:19:48 +0000
+++ pkg/dem/Engine/GlobalEngine/CohesiveFrictionalContactLaw.cpp	2010-10-13 15:04:25 +0000
@@ -64,10 +64,6 @@
 	               || currentContactPhysics->normalAdhesion==0)) {
 		// BREAK due to tension
 		scene->interactions->requestErase(contact->getId1(),contact->getId2());
-		// contact->phys was reset now; currentContactPhysics still hold the object, but is not associated with the interaction anymore
-// 			currentContactPhysics->cohesionBroken = true;
-// 			currentContactPhysics->normalForce = Vector3r::ZERO;
-// 			currentContactPhysics->shearForce = Vector3r::ZERO;
 	} else {
 		State* de1 = Body::byId(id1,scene)->state.get();
 		State* de2 = Body::byId(id2,scene)->state.get();
@@ -90,10 +86,8 @@
 			if (currentContactPhysics->fragile && !currentContactPhysics->cohesionBroken) {
 				currentContactPhysics->SetBreakingState();
 				maxFs = max((Real) 0, Fn*currentContactPhysics->tangensOfFrictionAngle);
-				
 			}
 			maxFs = maxFs / Fs;
-			if (maxFs>1) cerr << "maxFs>1!!" << endl;
 			shearForce *= maxFs;
 			if (Fn<0)  currentContactPhysics->normalForce = Vector3r::Zero();//Vector3r::Zero()
 		}

=== modified file 'pkg/dem/Engine/GlobalEngine/CohesiveFrictionalContactLaw.hpp'
--- pkg/dem/Engine/GlobalEngine/CohesiveFrictionalContactLaw.hpp	2010-09-30 18:00:41 +0000
+++ pkg/dem/Engine/GlobalEngine/CohesiveFrictionalContactLaw.hpp	2010-10-13 15:04:25 +0000
@@ -16,7 +16,7 @@
 class Law2_ScGeom_CohFrictPhys_ElasticPlastic: public LawFunctor{
 	public:
 	virtual void go(shared_ptr<IGeom>& _geom, shared_ptr<IPhys>& _phys, Interaction* I);
-	YADE_CLASS_BASE_DOC_ATTRS(Law2_ScGeom_CohFrictPhys_ElasticPlastic,LawFunctor,"Law for linear traction-compression-bending-twisting, with cohesion+friction and Mohr-Coulomb plasticity surface. Can be elastic-fragile or perfectly elastic-plastic. Creep at contact can be enabled.\n\n.. note::\n This law uses :yref:`ScGeom`.",
+	YADE_CLASS_BASE_DOC_ATTRS(Law2_ScGeom_CohFrictPhys_ElasticPlastic,LawFunctor,"Law for linear traction-compression-bending-twisting, with cohesion+friction and Mohr-Coulomb plasticity surface. This law adds adhesion and moments to :yref:`Law2_ScGeom_FrictPhys_Basic`.\n\nThe normal force is (with the convention of positive tensile forces) $F_n=min(k_n*u_n, a_n)$, with $a_n$ the normal adhesion. The shear force is $F_s=k_s*u_s$, the plasticity condition defines the maximum value of the shear force, by default $F_s^{max}=F_n*tan(\\phi)+a_s$, with $\\phi$ the friction angle and $a_n$ the shear adhesion. If :yref:`CohFrictPhys::cohesionDisableFriction` is True, friction is ignored as long as adhesion is active, and the maximum shear force is only $F_s^{max}=a_s$.\n\nIf the maximum tensile or maximum shear force is reached and :yref:`CohFrictPhys::fragile` =True (default), the cohesive link is broken, and $a_n, a_s$ are set back to zero. If a tensile force is present, the contact is lost, else the shear strength is $F_s^{max}=F_n*tan(\\phi)$. If :yref:`CohFrictPhys::fragile` =False (in course of implementation), the behaviour is perfectly plastic, and the shear strength is kept constant.\n\nIf :yref:`Law2_ScGeom_CohFrictPhys_ElasticPlastic::momentRotationLaw` =True, bending and twisting moments are computed using a linear law with moduli respectively $k_t$ and $k_r$ (the two values are the same currently), so that the moments are : $M_b=k_b*\\Theta_b$ and $M_t=k_t*\\Theta_t$, with $\\Theta_{b,t}$ the relative rotations between interacting bodies. There is no maximum value of moments in the current implementation, though they could be added in the future.\nCreep at contact is implemented in this law, as defined in [Hassan2010]_ can be activated. In this case, there is a viscous behaviour of the shear and twisting components, and the evolution of the elastic parts of shear displacement and relative twist is given by $du_{s,e}/dt=F_s/\\nu_s$ and $d\\Theta_{t,e}/dt=M_t/\\nu_t$.",
 		((bool,neverErase,false,,"Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. :yref:`Law2_ScGeom_CapillaryPhys_Capillarity`)"))
 		((bool,momentRotationLaw,false,,"use bending/twisting moment at contacts. See :yref:`CohFrictPhys::cohesionDisablesFriction` for details."))
 		((bool,always_use_moment_law,false,,"If true, use bending/twisting moments at all contacts. If false, compute moments only for cohesive contacts."))

=== modified file 'pkg/dem/Engine/GlobalEngine/ElasticContactLaw.hpp'
--- pkg/dem/Engine/GlobalEngine/ElasticContactLaw.hpp	2010-09-30 18:00:41 +0000
+++ pkg/dem/Engine/GlobalEngine/ElasticContactLaw.hpp	2010-10-13 15:04:25 +0000
@@ -22,7 +22,7 @@
 		Real elasticEnergy ();
 		Real getPlasticDissipation();
 		void initPlasticDissipation(Real initVal=0);
-		YADE_CLASS_BASE_DOC_ATTRS_CTOR_PY(Law2_ScGeom_FrictPhys_Basic,LawFunctor,"Law for linear compression, without cohesion and Mohr-Coulomb plasticity surface.\n\n.. note::\n This law uses :yref:`ScGeom`; there is also functionally equivalent :yref:`Law2_Dem3DofGeom_FrictPhys_Basic`, which uses :yref:`Dem3DofGeom` (sphere-box interactions are not implemented for the latest).",
+		YADE_CLASS_BASE_DOC_ATTRS_CTOR_PY(Law2_ScGeom_FrictPhys_Basic,LawFunctor,"Law for linear compression, and Mohr-Coulomb plasticity surface without cohesion.\nThis law implements the classical linear elastic-plastic law from [CundallStrack1979]_ (see also [Pfc3dManual30]_). The normal force is (with the convention of positive tensile forces) $F_n=min(k_n*u_n, 0)$. The shear force is $F_s=k_s*u_s$, the plasticity condition defines the maximum value of the shear force : $F_s^{max}=F_n*tan(\\phi)$, with $\\phi$ the friction angle.\n\n.. note::\n This law uses :yref:`ScGeom`; there is also functionally equivalent :yref:`Law2_Dem3DofGeom_FrictPhys_Basic`, which uses :yref:`Dem3DofGeom` (sphere-box interactions are not implemented for the latest).\n\n.. note::\n This law is generalised by :yref:`Law2_ScGeom_CohFrictPhys_ElasticPlastic`, which adds cohesion and moments.",
 		((bool,neverErase,false,,"Keep interactions even if particles go away from each other (only in case another constitutive law is in the scene, e.g. :yref:`Law2_ScGeom_CapillaryPhys_Capillarity`)"))
 		((bool,traceEnergy,false,,"Define the total energy dissipated in plastic slips at all contacts."))
 		,,