Creating a rigid face

[Anonymous]

I'd like a cross section one of my parts to remain rigid during an LSS simulation. Specifically, I'm applying a torque and want to prevent warping in this cross section. 

To accheive this I am duplicating the lines on the desired face and generating beam elements. I then assign them a steel material property (ASTM steel bar) with the default I-beam cross section.

Is this a valid method of creating a rigid face? Are there Ibeam cross sections or material choices that would generate more accurate results than the default I-beam and ASTM steel?

Thank you,
Shannon