yade-dev team mailing list archive

[Bruno Chareyre <bruno.chareyre@xxxxxxxxxxx>]

Hi,

I'm wondering if the stiffness overstimate is not actually a strain 
underestimate due to the "linear" strain.
Example :

refSize=1
after cloud compression : size=0.6

targetStress=1;
stiffness=100;

convertedLinearStrain = 1/100*refSize = 0.01
newSize = 0.59

Consequence : this strain increment is actually not 0.01.
You can even see that using the small strain approximation with current 
size  :

strain = (0.59-0.60)/0.6 = -1.66e-2

or the log strain :

log(.59)-log(0.6)= -1.68e-2

And the stress increment caused by this deformation is really ds = 
1.68*stiffness.

Bruno

p.s. I'm teaching all afternoon. See you later.


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Chareyre Bruno
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