# What will be reset when I switch from Mohr-coulomb model to Strain-softening?

**URL:** <https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398>\
**Category:** FLAC\
**Created:** [March 29, 2022, 12:21pm UTC](https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398 "2022-03-29T12:21:08Z")\
**Posts on this page:** 5\
**Page:** 1

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**Author:** ![FLAC3D\_GEO](https://avatars.discourse-cdn.com/v4/letter/f/f1d935/32.png) [@FLAC3D\_GEO](https://forum.itascainternational.com/u/FLAC3D_GEO)\
**Post date:** [March 29, 2022, 12:21pm UTC](https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398/1 "2022-03-29T12:21:08Z")

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Hi, Could anyone inside Itasca clarify what will be changed when I switch the soil model from mohr-coulomb to the strain-softening model in FLAC? In FLAC3D, it seems to me that the stress won’t reset, and I do not need to re-input the elastic properties or density. However, it seems to be different in FLAC?

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**Author:** ![cheng](https://avatars.discourse-cdn.com/v4/letter/c/ecccb3/32.png) [@cheng](https://forum.itascainternational.com/u/cheng)\
**Post date:** [March 29, 2022, 3:54pm UTC](https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398/2 "2022-03-29T15:54:06Z")

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No, even in FLAC3D you need to reset all properties - except density (if we consider density a property). Even two models have the same property names, e.g., shear, bulk, they need to be re-assigned after switching the constitutive model.

Stress and strain can be kept but of course you can re-initialize them.

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**Author:** ![FLAC3D\_GEO](https://avatars.discourse-cdn.com/v4/letter/f/f1d935/32.png) [@FLAC3D\_GEO](https://forum.itascainternational.com/u/FLAC3D_GEO)\
**Post date:** [March 30, 2022, 12:02am UTC](https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398/3 "2022-03-30T00:02:52Z")

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Thanks, Cheng! But clearly in FLAC3D, we do not need to re-assign shear and bulk (at least when switch from Mohr-Coulomb to SS). I checked the results, they remain the same as those were assigned before. By the way, I like this and it is more convenient.

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**Author:** ![cheng](https://avatars.discourse-cdn.com/v4/letter/c/ecccb3/32.png) [@cheng](https://forum.itascainternational.com/u/cheng)\
**Post date:** [March 30, 2022, 1:20am UTC](https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398/4 "2022-03-30T01:20:23Z")

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Weird! I just tested it. It’s not working for me. Which FLAC3D version are you using? Could you please share the datafile?

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**Author:** ![FLAC3D\_GEO](https://avatars.discourse-cdn.com/v4/letter/f/f1d935/32.png) [@FLAC3D\_GEO](https://forum.itascainternational.com/u/FLAC3D_GEO)\
**Post date:** [March 30, 2022, 1:49am UTC](https://forum.itascainternational.com/t/what-will-be-reset-when-i-switch-from-mohr-coulomb-model-to-strain-softening/398/5 "2022-03-30T01:49:20Z")

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Sorry, Cheng! False alarm. Anyway, it is useful for me to confirm density (and stress) are not reset.