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Bulk modulus for viscoelastic materials

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Hi, I noticed that the viscoelastic model only allow the inputs of shear modulus and relaxation time for the material properties. What about bulk modulus which is also a viscoelastic parameter? Any solutions to a viscoelastic bulk modulus? Thank you, -- Steve.

4 Replies Last Post Apr 29, 2014, 11:55 a.m. EDT
Nagi Elabbasi Facebook Reality Labs

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Posted: 1 decade ago Apr 27, 2014, 9:43 a.m. EDT
Hi Steve,

In the viscoelastic material only the deviatoric deformation is viscoelastic. The volumetric deformation is only elastic which is a reasonable assumption for most materials. The bulk modulus is therefore obtained from the base elastic material properties.

Nagi Elabbasi
Veryst Engineering
Hi Steve, In the viscoelastic material only the deviatoric deformation is viscoelastic. The volumetric deformation is only elastic which is a reasonable assumption for most materials. The bulk modulus is therefore obtained from the base elastic material properties. Nagi Elabbasi Veryst Engineering

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Posted: 1 decade ago Apr 28, 2014, 4:29 p.m. EDT
Hi Nagi, Thanks for your reply. What if I want to model a viscoelastic material with a time dependent bulk modulus, which may be the case for some geo-materials. Can you please give me any suggestions for this? Thank you again.--Steve


Hi Steve,

In the viscoelastic material only the deviatoric deformation is viscoelastic. The volumetric deformation is only elastic which is a reasonable assumption for most materials. The bulk modulus is therefore obtained from the base elastic material properties.

Nagi Elabbasi
Veryst Engineering


Hi Nagi, Thanks for your reply. What if I want to model a viscoelastic material with a time dependent bulk modulus, which may be the case for some geo-materials. Can you please give me any suggestions for this? Thank you again.--Steve [QUOTE] Hi Steve, In the viscoelastic material only the deviatoric deformation is viscoelastic. The volumetric deformation is only elastic which is a reasonable assumption for most materials. The bulk modulus is therefore obtained from the base elastic material properties. Nagi Elabbasi Veryst Engineering [/QUOTE]

Nagi Elabbasi Facebook Reality Labs

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Posted: 1 decade ago Apr 29, 2014, 12:24 a.m. EDT
You can switch to a volumetric creep model instead of viscoelasticity. You can also modify the viscoelastic equations to make the volumetric deformation viscoelastic. That is doable but not trivial.

Nagi Elabbasi
Veryst Engineering
You can switch to a volumetric creep model instead of viscoelasticity. You can also modify the viscoelastic equations to make the volumetric deformation viscoelastic. That is doable but not trivial. Nagi Elabbasi Veryst Engineering

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Posted: 1 decade ago Apr 29, 2014, 11:55 a.m. EDT
Thank you for your suggestions, Nagi.
Steve
Thank you for your suggestions, Nagi. Steve

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