Abaqus/Explicit: Dynamic failure models

[ShadowWarrior]

There are two simple models for Dynamic failure, TENSILE FAILURE and SHEAR FAILURE -

http://abaqus.ethz.ch:2080/v6.14/books/usb/default.htm?startat=pt05ch23s02abm24.html

So far what I understood, with element deletion ON -

*TENSILE FAILURE, ELEMENT DELETION=YES
[hydrostatic cutoff stress]
*SHEAR FAILURE, ELEMENT DELETION=YES
[equivalent plastic strain at failure]

My question is, how do I determine the hydrostatic cutoff stress parameter from a uni-axial tensile stress-strain data? The equivalent plastic strain at failure can be found as (Total strain - Elastic strain), right?

 

[rogersma]

I believe it is the first principal stress at which your material would fail. You could try using the stress from your tensile stress-strain data, assuming your data is given in engineering units, by noting the last point of the stress-strain curve where the derivative changes sign.

More info here