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[chiara modenese <c.modenese@xxxxxxxxx>]

Hello Bruno,

concerning viscous damping (I am quite interested in it since in the early
future, hopefully, I will deal with a dynamic problem) you said:

*****************
If spring and dashpot are in parallel it should be something like :

elasticShearF += shearVel*phys.ks*dt; //check plasticity condition on that
one ...
viscousShearF = shearVel*phys.cs;
shearForce = elasticShearF + viscousShearF; //... or that one, depends on
your constitutive model

The solid (elastic) force can accumulate with increments, the viscous one is
uniquely defined as a function of current velocity (no history).
*****************

I agree that if we have sliding we should not consider viscous damping but
only friction damping, but why would you check plasticity only on the shear
elastic part? I would check plasticity on the current shear force (without
damping) but actually taking into account the history of the elastic +
viscous shear force... And why do you say that the viscous force does not
have a history? It does since it depends on the velocities of the
particles...
Any thoughts?

Chiara