How to control the failure conditions in the triaxial compression

Hello,

>>I did not find how the DEVIATORIC LOADING stage controls the damage of the specimen.In other DEM software, it seems that the damage is controlled by breaking the bond between the particles.

I am not sure what "controls damage" means. But I will point out that there is no cohesion in [1], so no bonds to break. It is a simple frictional material, so that means there is also no "damage" model used in this script.

Cheers,

Robert

[1][1]https://gitlab.com/yade-dev/trunk/-/blob/master/examples/triax-tutorial/script-session1.py

Hello,Robert

What I mean is to simulate the triaxial compression failure process of the rock sample in the test.In actual compression, the failure ends with rock fragmentation (represented as peak value on the stress-strain image).

As you said, the material used in [1] is a simple frictional material so there is no damage,right?If so,as I said above, can you recommend me which material is more suitable for my purpose.Or where should I look for suitable materials? (Such as ’material library‘?)

Thanks for help.

Hello,

>>[1] is a simple frictional material so there is no damage,right?

It is a simple frictional material, so that means there is also no "damage" model.

>>can you recommend me which material is more suitable for my purpose

We have various cohesive models including CPMMat and JCFPMMat and CohFrictMat. They can be found in the class reference [1], or in the source code directly. I don't know "your purpose" so I can't really tell you which one is best. The best thing to do is for you to investigate these models yourself, since I guess you do know "your purpose". Investigation of these should probably include reading papers associated with them (e.g. [3]), reading the source code associated with them (e.g. [2][3]), and looking at other papers that have been written associated with them [4].

>>as I said above,

You did not say anything regarding a request for material recommendation before this.

Cheers,

Robert

[1]https://yade-dem.org/doc/yade.wrapper.html
[2]https://yade-dem.org/doc/yade.wrapper.html#yade.wrapper.Law2_ScGeom_JCFpmPhys_JointedCohesiveFrictionalPM
[3]https://gitlab.com/yade-dev/trunk/-/blob/master/pkg/dem/JointedCohesiveFrictionalPM.cpp#L2
[4]https://www.yade-dem.org/doc/publications.html

Hello,

I'm sorry for not express my purpose clearly.What I want to simulate is the mechanical properties of rock under the coupling of high temperature and seepage.So the first step for me is a triaxial compression test under normal conditions.
So, do you have any good recommendations about materials.(Excuse me, I'm not sure if this expression is enough..)

And then,I will follow your advice and investigate these models and try to find a suitable one.

Best regards.

Hello,

>>I want to simulate is the mechanical properties of rock under the coupling of high temperature and seepage

"Mechanical properties of rock" is quite a general statement. Rock modeling is a deep topic, and I do not believe a single model exists that contains all various aspects of rock behavior. Especially not any of our DEM contact laws. That said, you can model aspects of rock behavior with Yade, depending on which aspects you need to focus on.

Cheers,

Robert

Thank you for your patient explanation,Robert.
I will concretize my research content and carry out relevant learning and research in time.
That solved my problem.

Hi,

You can definitely use the JCFPM model for modeling rock like materials.

Please refer to previous questions/answers where you will find everything you need to perform a uniaxial compression test (you'll need to marginally adapt the script for triaxial tests).

See for instance:

https://answers.launchpad.net/yade/+question/694253

https://answers.launchpad.net/yade/+question/697724

Luc

Hi Luc,
Thanks for your help.I will study according to your suggestion.

Best regards.