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How to cause calculated strains from PDE for constitutive model
Posted Jul 17, 2013, 5:23 a.m. EDT Structural Mechanics Version 4.3b 1 Reply
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Hi everybody!
I have a quick question for you about implementation own constitutive model.
So my model describe shotcrete behaviour and it’s composed from several parts responsible for shrinkage, reversible creep, elastic behaviour which depend on current stress level etc.
I have used PDE to calculate strain and it works very well, to include elastic modulus which depend on the current stress level I used the stress from linear elastic model.
My question is how to cause these calculated strains in the model? Let say that I have values of scalars for each local direction. Is it good solution just to replace normal equations for linear elastic model under “equation view”? or there is better solution for it?
Thank you in advance for help!
I have a quick question for you about implementation own constitutive model.
So my model describe shotcrete behaviour and it’s composed from several parts responsible for shrinkage, reversible creep, elastic behaviour which depend on current stress level etc.
I have used PDE to calculate strain and it works very well, to include elastic modulus which depend on the current stress level I used the stress from linear elastic model.
My question is how to cause these calculated strains in the model? Let say that I have values of scalars for each local direction. Is it good solution just to replace normal equations for linear elastic model under “equation view”? or there is better solution for it?
Thank you in advance for help!
1 Reply Last Post Jul 17, 2013, 6:40 p.m. EDT
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Posted:
1 decade ago
Hi,
Some time ago when I had no structural mechanics module, and just linear elasticity, I had to solve a time dependent thermo-elastic problem.
In order to include thermal strain, I had then directly modified the stresses S11, S22 and S33 in linear elasticity equation view by appending to the existing equations an extra term -3.0*thermal_exp_coeff*(T-Tr)*solid.K in S11, 22 and 33 and clicked on 'Refresh equations'. I had got good comparison with an alternative code.
If this is what you meant.
Suresh
Some time ago when I had no structural mechanics module, and just linear elasticity, I had to solve a time dependent thermo-elastic problem.
In order to include thermal strain, I had then directly modified the stresses S11, S22 and S33 in linear elasticity equation view by appending to the existing equations an extra term -3.0*thermal_exp_coeff*(T-Tr)*solid.K in S11, 22 and 33 and clicked on 'Refresh equations'. I had got good comparison with an alternative code.
If this is what you meant.
Suresh