Hi,
Whenever I read explainations of the deformation gradient tensor (DGT) it is always with reguard to infinitesimal line segments.
Could anybody explain how this idea is expanded to obtain the DGT of a finite element?
For instance how would one go about constructing the DGT for a shell element? How would the principle stretches be obtained?
Thanks for any help with this (even if its just speculation).
B