# Interface Between Plate and Specimen Modeling

**URL:** <https://forum.itascainternational.com/t/interface-between-plate-and-specimen-modeling/1236>\
**Category:** 3DEC\
**Created:** [October 31, 2023, 5:37pm UTC](https://forum.itascainternational.com/t/interface-between-plate-and-specimen-modeling/1236 "2023-10-31T17:37:59Z")\
**Posts on this page:** 2\
**Page:** 1

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**Author:** ![Akash](https://avatars.discourse-cdn.com/v4/letter/a/a5b964/32.png) [@Akash](https://forum.itascainternational.com/u/Akash)\
**Post date:** [October 31, 2023, 5:37pm UTC](https://forum.itascainternational.com/t/interface-between-plate-and-specimen-modeling/1236/1 "2023-10-31T17:37:59Z")

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Hello,

I am trying to run UCS on cuboidal specimens (consisting of deformable tetrahedral blocks) of different width-to-height ratios in 3DEC. The goal is to calibrate all w/h ratios model peak strength with a single micro-property set. Therefore, I am trying to use the interface friction angle between the plate and specimen (to generate some confining stress due to boundary constraints). For that, I am creating the geometry first and then populating it with the tetrahedral blocks. After trimming the sides, I created the top and bottom plates using the brick command. I just want to confirm, is it the best way to create an interface between the plate and specimen or do I need to use some other commands to create the interface?

Thank you for your help.

[Generate\_w\_Platens.dat](https://forum.itascainternational.com/uploads/short-url/1kSBFG4YAD5VZBQoFdx045azrci.dat) (955 Bytes)

 ![picsetup](https://canada1.discourse-cdn.com/flex031/uploads/itasca/original/1X/6b4da38a12419ef38bf9637766ac0dd4741599c3.png)

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**Author:** ![jhazzard](https://avatars.discourse-cdn.com/v4/letter/j/4af34b/32.png) [@jhazzard](https://forum.itascainternational.com/u/jhazzard)\
**Post date:** [November 1, 2023, 1:51pm UTC](https://forum.itascainternational.com/t/interface-between-plate-and-specimen-modeling/1236/2 "2023-11-01T13:51:42Z")

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This looks fine. You can convince yourself that it is working by plotting the joint planes. You will see a continuous joint plane at the top and bottom between the platens and the voronois. You just need to assign the approriate contact properties to these planes.