Index: /issm/trunk/src/c/objects/Tria.cpp
===================================================================
--- /issm/trunk/src/c/objects/Tria.cpp	(revision 69)
+++ /issm/trunk/src/c/objects/Tria.cpp	(revision 70)
@@ -33,5 +33,5 @@
 
 Tria::Tria(int tria_id,int tria_mid,int tria_mparid,int tria_node_ids[3],double tria_h[3],double tria_s[3],double tria_b[3],double tria_k[3],
-				int tria_friction_type,double tria_p,double tria_q,int tria_shelf,double tria_meanvel,double tria_epsvel){
+				int tria_friction_type,double tria_p,double tria_q,int tria_shelf,double tria_meanvel,double tria_epsvel,double tria_viscosity_overshoot){
 	
 	int i;
@@ -60,4 +60,5 @@
 	epsvel=tria_epsvel;
 	onbed=1;
+	viscosity_overshoot=tria_viscosity_overshoot;
 	
 	return;
@@ -88,4 +89,5 @@
 	printf("   epsvel: %g\n",epsvel);
 	printf("   onbed: %i\n",onbed);
+	printf("   viscosity_overshoot=%g\n",viscosity_overshoot);
 	printf("   nodes: \n");
 	if(nodes[0])nodes[0]->Echo();
@@ -134,4 +136,5 @@
 	memcpy(marshalled_dataset,&meanvel,sizeof(meanvel));marshalled_dataset+=sizeof(meanvel);
 	memcpy(marshalled_dataset,&epsvel,sizeof(epsvel));marshalled_dataset+=sizeof(epsvel);
+	memcpy(marshalled_dataset,&viscosity_overshoot,sizeof(viscosity_overshoot));marshalled_dataset+=sizeof(viscosity_overshoot);
 	
 	*pmarshalled_dataset=marshalled_dataset;
@@ -161,4 +164,5 @@
 		+sizeof(meanvel)
 		+sizeof(epsvel)
+		+sizeof(viscosity_overshoot)
 		+sizeof(int); //sizeof(int) for enum type
 }
@@ -200,4 +204,5 @@
 	memcpy(&meanvel,marshalled_dataset,sizeof(meanvel));marshalled_dataset+=sizeof(meanvel);
 	memcpy(&epsvel,marshalled_dataset,sizeof(epsvel));marshalled_dataset+=sizeof(epsvel);
+	memcpy(&viscosity_overshoot,marshalled_dataset,sizeof(viscosity_overshoot));marshalled_dataset+=sizeof(viscosity_overshoot);
 
 	/*nodes and materials are not pointing to correct objects anymore:*/
@@ -292,7 +297,10 @@
 	/* material data: */
 	double viscosity; //viscosity
+	double newviscosity; //viscosity
+	double oldviscosity; //viscosity
 	
 	/* strain rate: */
 	double epsilon[3]; /* epsilon=[exx,eyy,exy];*/
+	double oldepsilon[3]; /* oldepsilon=[exx,eyy,exy];*/
 
 	/* matrices: */
@@ -318,5 +326,7 @@
 	/*input parameters for structural analysis (diagnostic): */
 	double* velocity_param=NULL;
+	double* oldvelocity_param=NULL;
 	double  vxvy_list[numgrids][2];
+	double  oldvxvy_list[numgrids][2];
 	double  thickness;
 
@@ -331,4 +341,5 @@
 	/*recover extra inputs from users, at current convergence iteration: */
 	velocity_param=ParameterInputsRecover(inputs,"velocity"); 
+	oldvelocity_param=ParameterInputsRecover(inputs,"old_velocity"); 
 
 	/* Get node coordinates and dof list: */
@@ -338,5 +349,4 @@
 	/* Set Ke_gg to 0: */
 	for(i=0;i<numdofs;i++) for(j=0;j<numdofs;j++) Ke_gg[i][j]=0.0;
-
 
 	/*Initialize vxvy_list: */
@@ -349,4 +359,13 @@
 			vxvy_list[i][0]=0;
 			vxvy_list[i][1]=0;
+		}
+
+		if(oldvelocity_param){
+			oldvxvy_list[i][0]=oldvelocity_param[doflist[i*numberofdofspernode+0]];
+			oldvxvy_list[i][1]=oldvelocity_param[doflist[i*numberofdofspernode+1]];
+		}
+		else{
+			oldvxvy_list[i][0]=0;
+			oldvxvy_list[i][1]=0;
 		}
 	}
@@ -443,7 +462,9 @@
 		/*Get strain rate from velocity: */
 		GetStrainRate(&epsilon[0],&vxvy_list[0][0],&xyz_list[0][0],gauss_l1l2l3);
+		GetStrainRate(&oldepsilon[0],&oldvxvy_list[0][0],&xyz_list[0][0],gauss_l1l2l3);
 		
 		/*Get viscosity: */
 		matice->GetViscosity2d(&viscosity, &epsilon[0]);
+		matice->GetViscosity2d(&oldviscosity, &oldepsilon[0]);
 		
 		/* Get Jacobian determinant: */
@@ -452,5 +473,7 @@
 		/* Build the D matrix: we plug the gaussian weight, the thickness, the viscosity, and the jacobian determinant 
 		   onto this scalar matrix, so that we win some computational time: */
-		D_scalar=viscosity*thickness*gauss_weight*Jdet;
+		newviscosity=viscosity+viscosity_overshoot*(viscosity-oldviscosity);
+		D_scalar=newviscosity*thickness*gauss_weight*Jdet;
+
 		for (i=0;i<3;i++){
 			D[i][i]=D_scalar;
Index: /issm/trunk/src/c/objects/Tria.h
===================================================================
--- /issm/trunk/src/c/objects/Tria.h	(revision 69)
+++ /issm/trunk/src/c/objects/Tria.h	(revision 70)
@@ -43,4 +43,5 @@
 		double epsvel; /*!minimum velocity to avoid infinite velocity ratios*/
 		int    onbed;
+		double viscosity_overshoot;
 	
 	public:
@@ -48,5 +49,5 @@
 		Tria();
 		Tria(int id,int mid,int mparid,int node_ids[3],double h[3],double s[3],double b[3],double k[3],
-				int friction_type,double p,double q,int shelf,double meanvel,double epsvel);
+				int friction_type,double p,double q,int shelf,double meanvel,double epsvel,double viscosity_overshoot);
 		~Tria();