How to model axial-flexural hinges in opensees

[linguan118]

The flexural hinge can be modelled using the moment-rotation spring.
But I wonder how to model axial-flexural hinges like those in SAP2000 where a yield moment- axial load interaction curve is predefined.
The moment rotation behavior varies according to the axial loads.
Thanks!

[linguan118]

I mean lumped plasticity element of course.

[vesna]

I believe that such code exists but unfortunately it is not documented. Look for it at the source code.

[mhscott]

SRC/material/yieldSurface. I really don't know if they work.

[kostast88]

For YieldSurface Orbison model example:

ysEvolutionModel null 100 1.0 1.0
yieldSurface_BC Orbison2D 100 1.0e12 1.0e12 100
section YS_Section2D01 1 $E $A $I 100

The rest of the models lies here:
https://nees.org/tools/openseescomp/bro ... ions2D.ops

However this is how the commands work,don't know either what they do, or how they work(even if they work correctly).

[linguan118]

Thank you for your replies!
Gotta read the source code myself.