This 'experiment' was purely for kicks and I just wanted to share with the group to see
1. if my assumptions are correct and/or
2. I just got lucky
I modeled a stainless steel rule (ie shop ruler, scale, etc). 250mm long x ~30mm wide x 1mm thick & ran a nonlinear
simulation (shell elements) with one end fixed and the other with a prescribed rotation of 180* (3.14 radians).
I'm sure most of you have seen this before. I didn't go to 360 as am somewhat attached to my (still straight) ruler.
I duplicated the test as best I could in my garage.. put the rule in a vise and used a force gage to bend it around
180*. I sort of eye balled things a bit, not very rigorous.. but again, just a curiosity.
See image attached.
SW Simulation predicted ~60 in-lbs reaction moment.
My measurement = ~ 58 in-lbs
So back to my question(s):
1. the simulation shows a purely circular deformed shape. I assume this is because I'm using shell elements,
have a constant moment through the beam.. and no stress calculated throughout its cross-section. ie.. only
the reactions would be valid -- true / false?
2. the 'real' test shows more of the 'parabolic' bending I'd expect. I don't think the angle or overshoot of my
force gage position should matter much in that I (think) I would always end up with the same reaction moment.
The image may not look like 180 rotation though I'm quite sure I managed as much. May be lens distortion from
camera.. or I lightened up a bit while trying to shoot with the other hand, but you're seeing max force reading at