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------------------------------------------------------------
revno: 3587
committer: Luc Sibille <luc.sibille@xxxxxxxxxxxxxxx>
timestamp: Thu 2015-02-12 12:14:24 +0100
message:
  add fragile parameter to CohFrictMat and redefine unpMax CohFrictPhys
modified:
  pkg/dem/CohesiveFrictionalContactLaw.cpp
  pkg/dem/CohesiveFrictionalContactLaw.hpp


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=== modified file 'pkg/dem/CohesiveFrictionalContactLaw.cpp'
--- pkg/dem/CohesiveFrictionalContactLaw.cpp	2014-10-15 06:44:01 +0000
+++ pkg/dem/CohesiveFrictionalContactLaw.cpp	2015-02-12 11:14:24 +0000
@@ -119,7 +119,7 @@
 		if ((-Fn)> phys->normalAdhesion) {//normal plasticity
 			Fn=-phys->normalAdhesion;
 			phys->unp = un+phys->normalAdhesion/phys->kn;
-			if (phys->unpMax && phys->unp<phys->unpMax)
+			if (phys->unpMax>=0 && -phys->unp>phys->unpMax)  // Actually unpMax should be defined as a function of the average particule sizes for instance
 				return false;
 		}
 		phys->normalForce = Fn*geom->normal;
@@ -275,6 +275,7 @@
 				contactPhysics->normalAdhesion = std::min(sdec1->normalCohesion,sdec2->normalCohesion)*pow(std::min(Db, Da),2);
 				contactPhysics->shearAdhesion = std::min(sdec1->shearCohesion,sdec2->shearCohesion)*pow(std::min(Db, Da),2);
 				geom->initRotations(*(Body::byId(interaction->getId1(),scene)->state),*(Body::byId(interaction->getId2(),scene)->state));
+				contactPhysics->fragile=(sdec1->fragile || sdec2->fragile);
 			}
 			contactPhysics->kn = Kn;
 			contactPhysics->ks = Ks;
@@ -292,6 +293,7 @@
 				contactPhysics->shearAdhesion = std::min(sdec1->shearCohesion,sdec2->shearCohesion)*pow(std::min(geom->radius2, geom->radius1),2);
 
 				geom->initRotations(*(Body::byId(interaction->getId1(),scene)->state),*(Body::byId(interaction->getId2(),scene)->state));
+				contactPhysics->fragile=(sdec1->fragile || sdec2->fragile);
 				contactPhysics->initCohesion=false;
 			}
 		}

=== modified file 'pkg/dem/CohesiveFrictionalContactLaw.hpp'
--- pkg/dem/CohesiveFrictionalContactLaw.hpp	2014-10-15 06:44:01 +0000
+++ pkg/dem/CohesiveFrictionalContactLaw.hpp	2015-02-12 11:14:24 +0000
@@ -32,6 +32,7 @@
 		((Real,etaTwist,-1.,,"Dimensionless twisting strength. If negative, twist moment will be elastic."))
 		((Real,normalCohesion,-1,,"Tensile strength, homogeneous to a pressure. If negative the normal force is purely elastic."))
 		((Real,shearCohesion,-1,,"Shear strength, homogeneous to a pressure. If negative the shear force is purely elastic."))
+		((bool,fragile,true,,"do cohesion disappear when contact strength is exceeded"))
 		((bool,momentRotationLaw,false,,"Use bending/twisting moment at contact. The contact will have moments only if both bodies have this flag true. See :yref:`CohFrictPhys::cohesionDisablesFriction` for details."))
 		,
 		createIndex();
@@ -52,7 +53,7 @@
 	YADE_CLASS_BASE_DOC_ATTRS_CTOR(CohFrictPhys,FrictPhys,"",
 		((bool,cohesionDisablesFriction,false,,"is shear strength the sum of friction and adhesion or only adhesion?"))
 		((bool,cohesionBroken,true,,"is cohesion active? Set to false at the creation of a cohesive contact, and set to true when a fragile contact is broken"))
-		((bool,fragile,true,,"do cohesion disapear when contact strength is exceeded?"))
+		((bool,fragile,true,,"do cohesion disappear when contact strength is exceeded?"))
 		((Real,kr,0,,"rotational stiffness [N.m/rad]"))
 		((Real,ktw,0,,"twist stiffness [N.m/rad]"))
 		((Real,maxRollPl,0.0,,"Coefficient of rolling friction (negative means elastic)."))
@@ -60,7 +61,7 @@
 		((Real,normalAdhesion,0,,"tensile strength"))
 		((Real,shearAdhesion,0,,"cohesive part of the shear strength (a frictional term might be added depending on :yref:`CohFrictPhys::cohesionDisablesFriction`)"))
 		((Real,unp,0,,"plastic normal displacement, only used for tensile behaviour and if :yref:`CohFrictPhys::fragile` =false."))
-		((Real,unpMax,0,,"maximum value of plastic normal displacement, after that the interaction breaks even if :yref:`CohFrictPhys::fragile` =false. The default value (0) means no maximum."))
+		((Real,unpMax,0,,"maximum value of plastic normal displacement (counted positively), after that the interaction breaks even if :yref:`CohFrictPhys::fragile` =false. A negative value (i.e. -1) means no maximum."))
 		((bool,momentRotationLaw,false,,"use bending/twisting moment at contacts. See :yref:`Law2_ScGeom6D_CohFrictPhys_CohesionMoment::always_use_moment_law` for details."))
 		((bool,initCohesion,false,,"Initialize the cohesive behaviour with current state as equilibrium state (same as :yref:`Ip2_CohFrictMat_CohFrictMat_CohFrictPhys::setCohesionNow` but acting on only one interaction)"))
 		((Real,creep_viscosity,-1,,"creep viscosity [Pa.s/m]."))