## General Mechanical

#### Cohesion with friction

• Lambrescu
Subscriber

Hello,

I have the following problem:

I want to model the contact between two bodies. I know how to model delamination (with CZM material), but I would like to model a situation where after the delamination occurs, the bodies in contact interact with friction.

To be more clear, after body 1 and body 2 loose cohesion, since there is a normal force (F) there is friction between them.

Is it possible to model that in Ansys Workbench?

man

• 1shan
Ansys Employee
After de-bonding is completed the surface interaction is governed by standard contact constraints for normal and tangential directions (the contact behavior at that interface is changed to standard contact (KEYOPT(12) = 0) by default). Frictional contact is used if friction is specified for contact elements.Check this 13.3. Post-Debonding Behavior of Cohesive Zone Material. Also ANSYS staff are not allowed to download attachments. Please insert inline images to support your query.

Regards Ishan.
• Lambrescu
Subscriber
Thank you Ishan for your answer and accept my excuses for replying so late.
The problem is that if I use CZM, the only contact accepted is Bonded. In these circumstances, how can I specify friction?
Many thanks
Ionut
• Lambrescu
Subscriber
Hello I am back. The documentation includes the following text:
When friction is defined between contact surfaces undergoing debonding, tangential stress is calculated as the maximum between the tangential stress as governed by the debonding model and the tangential stress as governed by the friction law.
If I am using CZM, the contact should be of type Bonded. For a Bonded contact, in Workbench I cannot define a friction coefficient, so how is possible to calculate the "tangential stress .. as the maximum between the tangential stress as governed by the debonding model and the tangential stress as governed by the friction law". What Friction law??
Should I use a Command in Workbench?
Kind regards Ionut
• ali.ismail
Subscriber

I'm using a student version of Ansys workbench and I have the problem of "The solver engine was unable to converge on a solution" while using Mohr-Coulomb to define a soil with very low cohesion. I will be very grateful if anyone tells me what to do asap