Ever so often, I am reminded that I r edumacated and that my classical structural geology education isn’t so meaningless in the larger scheme of my life:
JRSB recently said, “Get on into the wayback machine: can you give me a dummy breakdown of what the reduced modulus is versus the elastic modulus? The software is doing everything but wipe my butt for me, and I’m okay with that for the purposes of these tests, but I’d like to be able to understand the meaning of the reduced modulus. Help please.”
You’re asking me to think in terms of stress as opposed to strain for which you owe me not one, but two, Greenbush donuts, Mr. B.
Ahem … (assume ComicBookStoreGuy voice) …
Basically, it is the difference between elastic and inelastic deformation, or as the engineers like to call it, buckling. The elastic (Young’s) modulus is related to elastic buckling, but this only works for materials of an optimal length and orientation. In reality, elasticity is not the case (surprise, surprise!) and we are left with inelastic buckling. Now, the Young’s modulus is not going to turn out as predicted for elastic deformation and will _reduce_ to a value based on the tangent at the point when exceeding the local limit. So, the reduced modulus is the new Young’s modulus for your particular inelastic curve.
I strongly recommend calculating the load on your titanium dioxide with both Young’s and reduced moduli, and contrasting your difference. Just googled a nice set of graphs for you as well:
Look, ma, no hands!
