CZM Contact Modeling

Michele Furno

Hello everyone,

I am learning hyperworks and I really like its capability in term of composite modeling. 

Since in the application I have to study there are some metal inserts, I am struggling with the modeling of the interface between these two components.

In particular, most of the insert are adhesively bonded with the composite, and another part of them are glued after the curing process. In order to not increase the complexity of the model I decided to use the CZM model via contact.

I find some experimental data and the characterization of che damage curve of the adhesive, so I have all the parameters needed in the DMGINI and DMGEVO cards. Their values are similar to the one present in the Optistruct Guide Examples. 

To validate the model I am trying to model a simple Single Lap shear test. The problem Is that, since the Contact type has to be "Frictionless and Small Sliding", the two plates of the single Lap just separate, leading to a infinite deformation 6e9.

How can i set up properly the contact in a way that it actually constrain the model?

Just for clarity, I am not really interested in nonlinear analisys, I Just want to introduce the adhesive in term of stiffness of the Contact, so Just utilize the Kn and Kt in the linear analisys. In a similar way I usually modeled adhesive with other FEA software, and I was able to read the tangential and normal stresses on the contact area to detect if the bonding Is leading to failure.

If anyone can help me I will be happy, and I am open to any suggestion on other ways to model the adhesive for my application.

Thank you very much.

 

Rajashri_Saha

Hi Michele,

From your description it looks like you are working on contact based CZM technique. As the deformation is very high you need to do use Large displacement method.

I think you might be knowing there is also element based technique where you can model the adhesive and do the simulation.

I am attaching few docs and two models which you can refer for set up and explanation of CZM method.

Hope you find this helpful.

Thanks

Rajashri