Modeling SMAs in ABAQUS

Hi Dear fellow Mechanicians

I am Ali Nojoumi a M.Sc. Civil engineer and I'm modleing shape memory alloys using in concrete shear walls to reduce the effects of earthquakes...

making my Model by ABAQUS, I should use UserSubroutine to define such SuperElastic behavior How can I manage that and   have anyone ever done this?

I would be glad to have your suggestions or any contribution.

thanks alot; AliNojumi@GMAIL