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Re: Re : Triaxial Test


If you generated a
simulation where you have 1 box, filled with spheres inside, it would all
totally explode, because spheres would behave is if they were INSIDE a
solid box.

But... I thought ImpactTest was generated using a box...
Ok, I see : in fact it uses 6 boxes...
There is a simpler way to represent a wall-boudary : a finite or infinite plane, no need to assign it mass/thickness, stiffness is enough. I had almost the same idea when I thought to _*one*_ box for the triax. I will probably implement one of the two solutions (if not both) in the future.

First (simplest
approach) will add Stiffness without checking whether it is a sphere or
a wall, so all spheres will also have their total contact stiffness
summed, not only the walls.

In fact the total contact stiffness of a sphere is needed to compute accuretly the critical time-step (Tc). I remember I was a bit puzzled when I looked how Tc is currentmy computed in Yade (but I can't remember exactly). So, perhaps it is not a bad thing after all to compute the total stiffness of spheres. The method I know to evaluate Tc is based on the matrix Mij so that dRi = Mij*Uj (where Ri is the resultant and Uj the displacement of the sphere).

3. once you have Stiffness in physicalActionContainer - you can access
it from you DeuxEx just like you can access Force.

this was a brief explanation of the idea which I have in mind. tell me
if you understand it :)
I understand the overall idea, but I am not sure I understand precisely this line (from ForceEngine.cpp) :

static_cast<Force*>( ncb->actionParameters->find( b->getId() , actionParameterForce->getClassIndex() ).get() )->force += force;

Could you comment a bit on this?

I feel a small temptation to do it myself,
because it's interesting. But I have also other work to do (lattice and

I must learn to do the job myself. If not, I will never take advantages from using Yade :).
Your help is invaluable, it should be enough :).

it is
easier to modify .pro files by hand (for example with F4 from mc), than
to edit them with kdevelop3. (kdevelop3 displays scopes in a weird
manner, so better ignore it - I hope that they will fix this in near
"F4 from mc" ???!

As a general rule - when you work with yade - it is better to add new
classess than to modify existing ones :).
Of course. When I say "modify" (previous mails), I think copy/paste in new file and modify.

"Error: Could not open /dev/nvidiactl because the permissions
I know how to solve it temporarily (chmod on OGL files each time I start a KDE session).
I just change
in udev.permissions. It should fix the problem (I did not check yet).
Do you have an idea if this may be due to Yade?!

your fix works,

In fact it does not apparently :-(.
I will try what you recommend. But note that the problem is still here after I uninstalled the last version and re-installed the "official release".

Chareyre Bruno
     Maître de conférence
     Institut National Polytechnique de Grenoble
     Tél :
________________________________________ bureau I 08 Laboratoire 3S (Soils Solids Structures) BP 53 - 38041, Grenoble cedex 9 - France _______________

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