Deformable block - Model mohr-coulomb assigned to 0 zones

Hello everyone,

I made my model by importing several files in (.wrl) format.
I would like to transform only some blocks into deformable and leave the rest rigid.
I have no problems in fact as you can see, by assigning the size of the mesh I get that the desired blocks have been transformed into deformables (Fig.1).
The problem I have when I have to assign properties to these deformable blocks in fact using the command “block zone cmodel assign mohr-coulomb” I get that “Model mohr-coulomb assigned to 0 zones” (Fig.2).

Can you help me?
Thanks in advance.


as per the message in your console screenshot, zones and sub-contacts are only actually generated after an edge length has been provided for all blocks, and you can’t assign a constitutive model until the zoning is complete.

i don’t know if it’s actually possible to have a mixture of deformable and rigid blocks, but based on the above zoning logic, i would guess not. perhaps @jhazzard can advise?

assuming it’s not possible. for the blocks you would like to be rigid, why don’t you just assign them an elastic constitutive model, and extremely high strength/stiffness properties (orders of magnitude higher than the other blocks)?

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According to 3DEC manual, it is not possible to mix rigid and deformable blocks. See screenshot attached.


@Damir Ohh yes you can. Yes you start with creating a rigid block, then before assigning constitutive model you need to convent it into a deformable block with commands like “block zone generate edgelength……”.then after assign constitutive model.

@RockEugieK is correct. Officially it is not supported, but you can actually mix rigid and deformable. You just have to be a bit careful about assigning properties (i.e. you can’t assign zone properties to rigid blocks). Helpful tip: if you want to turn a zoned block into a rigid block, export it (block list poly range …), delete it, and then reimport it.

@RockEugieK and @jhazzard,

Thanks so much for the reply!