Hello All, 

I am working on a cohesive zone model, I am using cohesive contact with damage. My simulation shows a non-zero damage initiation value during a pure compressive state of the simulation. According to documentation and literature, in traction-separation law, I don't expect any initiation in a compressive state. Do you have any idea about this issue? I am adding few pictures to help you to understand my case. 

The shared plot shows the damage initiation criteria vs time and contact stress vs time. As you see pure contact pressure initiate the damage, this is the statement from documentation ; 

''Cohesive surfaces do not undergo damage under pure compression.'' 

Best,
Thank you in advance.

Salih