Main Question or Discussion Point
Why theories of failure have been developed from 1-D tensile testing. Why can't we go 2-D testing or 3-D testing?
I have a just simple question why theories of faliure was developed for 2-D and 3-D failure??There was recent work on why bent spaghetti shatters rather than 'just' snaps.
IIRC, they found that applying torsion to um, pre-stress it made it snap clean when bent...
Per OP's query, I think the answer lies in the study of 'fatigue', where unfortunate shape concentrates flexure damage to initiate failure. Once that begins, a simpler model may approximate...