Topic: 3D Nonlinear Cememtitious 2 Input Parameters Full Information

Hello,

I have been using ATENA 2D for a few years as a PhD student and I am trying to refine some models I have of low-rise shear walls. Overall, I have had good success, but I was wondering if is there is any documentation that clearly lists all of the input parameters of 3D Nonlinear Cementitious 2 and their effect on the material model behavior and constitutive equations? While some of the images are helpful, more detailed explanations of some of the parameters in the Tension, Compression, and Shear tabs would be helpful for this refinement.

Thanks!

Re: 3D Nonlinear Cememtitious 2 Input Parameters Full Information

Hello rdevine,

I am starting with ATENA 2D recently and am also trying to model some RC walls, however I am not having success modelling walls from literature, typically I experience failure much before peak load. I have modeled some beams and columns and they work fine. Do you have some suggestions?

Also, if possible could you please share a typical shear wall modelling file in ATENA. That would be of great help. Thank you.

Regards,
Sumedh

Re: 3D Nonlinear Cememtitious 2 Input Parameters Full Information

Dear rdevine,
it is not clear from your question if you have already looked into the ATENA Theory Manual? I recommend not only section 2.2 Fracture–Plastic Constitutive Model (CC3DCementitious, CC3DNonLinCementitious, CC3DNonLinCementitious2, CC3DNonLinCementitious2User, CC3DNonLinCementitious2Variable, CC3DNonLinCementitious2SHCC, CC3DNonLinCementitious3), but also 2.1 Constitutive Model SBETA (CCSbetaMaterial), as some things which are the same for both material model families are only explained in the SBETA section.

Regards.

Re: 3D Nonlinear Cememtitious 2 Input Parameters Full Information

Dear Sumedh,
1. it is not clear from your question if you have already checked for the most common problem sources as discussed in ATENA Troubleshooting, 2.2.18 My analysis results do not match the experiment/expectations. How can I improve my model?

2. I recommend to see the shear wall example included in ATENA installation - see the ATENA Engineerign Example Manual, 2.10 Shear wall with opening (SWO).

Regards.

Re: 3D Nonlinear Cememtitious 2 Input Parameters Full Information

Hello,

I'm making some simple models (with 1 element of 4 nodes) to better understand the material Cementitious2.

When simulating a plane state of stress, I tried to check if the peak stress in compression falls above the Menetrey-Willam's curve (considering sigma1=0 and sigma2 and sigma3 < 0).
I was hoping that the equibiaxial concrete strength (fbc) were equal to (1.2 x f'c), however the value I've got was (1.07 x f'c).
The excentricity was set equal to 0.52.

When simulating biaxial compression with the material model SBETA, the peak stresses agreed with the Kupfer formulation presented in ATENA Theory Manual, but I'm having this problem understanding what could have happened with Cementitious2.
Any suggestions?

Best regards,
Marcos

Re: 3D Nonlinear Cememtitious 2 Input Parameters Full Information

Can you please send your model and question to cervenka@cervenka.cz

Re: 3D Nonlinear Cememtitious 2 Input Parameters Full Information

sure. thanks