Composite crushing + CZONE application

Hello,

I am modelling a crushing simulation of a composite corrugated coupon using Abaqus/Explicit and CZONE Abaqus' application.

I am modeling the coupon using S4R elements and the impactor as a discrete rigid shell plate with a slow constant crushing speed or high initial velocity for quasi-static and dynamic crushing simulations respectively.

I am using Hashin damage in Abaqus/Explicit and Hashin and also Tsai-Wu on CZONE application.

1 - Should the compressive strengths in damage initiation have negative values or should I use only positive values for both tensile and compressive material strengths?

2 - When I use continuum shell elements instead of conventional shell elements using the same conditions I have different results of normal forces. Does anybody knows why?

3 - Does anybody have documentation, articles or examples about CZONE Abaqus' application?

Thank you for your help and understanding.

Best regards

David Melo