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[Chiara Modenese <chiara.modenese@xxxxxxxxx>]

Hi Bruno,


I would need your help concerning the Triaxial. Since I need a 
specific value of final porosity, I am trying to do something in your code but 
without success (BTW, I DON'T want to modify your code, if it will work I will 
manage to add a flag or something like that).
Let's I am using the expansion 
method, I have tried to do what it has been done in terms of stresses to get 
the final packing in terms of porosity as:


else //if internal compaction
{
	
if (isARadiusControlIteration) {

                      if (porosity>0.60) 
previousMultiplier = maxMultiplier;
                      else{

                              	previousMultiplier = 1. + fabs(n_fin - porosity)
/n_fin*(maxMultiplier-1.);
                        }
		      if 
(porosity<=n_fin) {
				Unb = ComputeUnbalancedForce(ncb);
(1)				if (Unb > 
0.1) previousMultiplier = 1.0;}

			previousStress = meanStress;
			
controlInternalStress(ncb, previousMultiplier);
	}
}


so basically in the line 
(1) it is like saying "cycle" without expanding if the value of Unb force is 
too high. Unfortunately "cycling" doesn't help (why? Should it?), the computed 
unbalanced force is always very high and around 1.
Could you give me any 
suggestions or directions how to do that? I mean, how to fix the value of final 
porosity..
Actually I remember you suggested me to play with the friction angle 
but I don't remember exactly.. 
I have got that having a specific PSD and a 
friction angle we can get only one possible value of final porosity (or a very 
small range of it) and that's true with the DEM (cause we are dealing with 
spheres and not irregular shapes) but to me it is always possible to say that 
for the same PSD I would like to run the Triaxial with an higher porosity 
(higher than that maximum dense packing I get with this method either with 
compaction or expansion).


Merci beaucoup.


Chiara


PS: Concerning your 
guess around the visualization of the force network, I remember Vaclav answered 
something like:

type in Dem3DofGeom_SphereSphere,cpp
bool 
Gl1_Dem3DofGeom_SphereSphere::normal=true

then in the mask the combination of 
Interaction_Geometry and intrAllWire should give the network (not sure, I have 
to try it again)