different NL material models for compression and tension

[yasmind]

Hi everone,

I am modeling a timber frame with brickwork infill, and was wondering how I can define two different nonlinear material models in compression and in tension (for brickwork). I am experiencing convergence problems and I believe this is due to material models. Any suggestion about this?

Thanks in advance.

[AstroJohnPE]

Hi yasmind,

It might be helpful if you could explain what material properties differ in tension versus compression.

Otherwise, you cannot assign two different material models to the same part. So the options that come to mind are as follows:

• Use a material model that allows input of compression and tension material properties, such as concrete.
• If the part has a clear division between what's in compression and what's in tension, such as what occurs when a beam is bent, the split the part into two parts. Then assign the appropriate material properties to each part.

[yasmind]

Hi John,

Thank you for your reply.

I am trying to model the brick infill (unreinforced masonry) as realistically as possible and in the relevant literature there are quite a number of work, where the unreinforced masonry was modelled using Drucker-Prager in compression and Rankine in tension. I wanted to try to do the same in my model, but given that this is not possible in Autocad Simulation I will think on concrete option and write again.

Cheers,

yasmind