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soil plasticity in poroelasticity

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I am doing a project using poroelasticity interface, but I wan to consider plasticity behavior of porous materials, so I need to use plasticity constitutive model for porous materials. How do I add soil plasticity model into the poroelasticity module. Can I self define plasticity constitutive model for the porous materials in the poroelasticity module? Thanks.

6 Replies Last Post Nov 10, 2016, 10:09 p.m. EST

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Posted: 1 decade ago May 27, 2013, 2:29 p.m. EDT
Anybody knows something about that?
Anybody knows something about that?

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Posted: 1 decade ago May 28, 2013, 12:09 p.m. EDT
Hi,


I see that plasticity is not accessible from poroelasticity.

Alternatively, could you not start with a nonlinear structural mechanics module and modify the equation in linear elasticity to reflect pore water pressure changes so that you can then use plasticity. In other words, you will have to add the term alpha*p*I into the term solid.S11, solid.S22, and solid.S33, where alpha is the Biot coefficient. I is the identity so you add it to diagonal elements only as above. Or probably you could introduce this term in the body load?

Test it.


Suresh

Hi, I see that plasticity is not accessible from poroelasticity. Alternatively, could you not start with a nonlinear structural mechanics module and modify the equation in linear elasticity to reflect pore water pressure changes so that you can then use plasticity. In other words, you will have to add the term alpha*p*I into the term solid.S11, solid.S22, and solid.S33, where alpha is the Biot coefficient. I is the identity so you add it to diagonal elements only as above. Or probably you could introduce this term in the body load? Test it. Suresh

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Posted: 1 decade ago Aug 21, 2013, 10:53 a.m. EDT
Hi Suresh

Thanks a lot for your suggestions.

I understand your meaning. But I still have a problem why plasticity can not be considered in poroelasticity module. In my point of view, the poroelasticity module is the combination of solid mechanics and Darcy's law. I think plasticity can be used in solid mechnics, why it can not be used in the combined module? Thanks.


Hi,


I see that plasticity is not accessible from poroelasticity.

Alternatively, could you not start with a nonlinear structural mechanics module and modify the equation in linear elasticity to reflect pore water pressure changes so that you can then use plasticity. In other words, you will have to add the term alpha*p*I into the term solid.S11, solid.S22, and solid.S33, where alpha is the Biot coefficient. I is the identity so you add it to diagonal elements only as above. Or probably you could introduce this term in the body load?

Test it.


Suresh

Hi Suresh Thanks a lot for your suggestions. I understand your meaning. But I still have a problem why plasticity can not be considered in poroelasticity module. In my point of view, the poroelasticity module is the combination of solid mechanics and Darcy's law. I think plasticity can be used in solid mechnics, why it can not be used in the combined module? Thanks. [QUOTE] Hi, I see that plasticity is not accessible from poroelasticity. Alternatively, could you not start with a nonlinear structural mechanics module and modify the equation in linear elasticity to reflect pore water pressure changes so that you can then use plasticity. In other words, you will have to add the term alpha*p*I into the term solid.S11, solid.S22, and solid.S33, where alpha is the Biot coefficient. I is the identity so you add it to diagonal elements only as above. Or probably you could introduce this term in the body load? Test it. Suresh [/QUOTE]

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Posted: 1 decade ago Aug 22, 2013, 7:56 a.m. EDT
Hi,


I understand your point, but you need to ask the support team.


Suresh
Hi, I understand your point, but you need to ask the support team. Suresh

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Posted: 10 years ago Apr 13, 2015, 3:26 p.m. EDT
All you need to do is to go to the Equation View and remove the "pf" from the diagonal terms of poroelastic stress tensor. That way, all the stress components will be effective stresses. Now if you add a plastic material, it should be analysed in effective stress or in other words, poroplasticity. Method 2: is to create Darcy Law with PDE and couple that with solid mechanics and your choice of plasticity constitutive model.
All you need to do is to go to the Equation View and remove the "pf" from the diagonal terms of poroelastic stress tensor. That way, all the stress components will be effective stresses. Now if you add a plastic material, it should be analysed in effective stress or in other words, poroplasticity. Method 2: is to create Darcy Law with PDE and couple that with solid mechanics and your choice of plasticity constitutive model.

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Posted: 8 years ago Nov 10, 2016, 10:09 p.m. EST
Hi to all,
What i think is that we can add plasticity in poroelasticity physics by adding the Linera elastic node first and under that we can add plasticity and other related. which is similar like in solid mechanics.
Hi to all, What i think is that we can add plasticity in poroelasticity physics by adding the Linera elastic node first and under that we can add plasticity and other related. which is similar like in solid mechanics.

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