Hi all!

I read that the "cmplementary starin energy of a structure is not equal to sum of the complementary strain energies of it's components, if there is non-linearity like geometric"

That means for e.g. if I consider a truss stucture subjected to loading so that it undergoes geometric non-linearity, then the sum of the complementary strain energies from members is not equal to complementary strain energy of the structure.

 I request somebody to explain why is it so??

 Thanks and regards,

- Ramdas

Checking the iMechanica web, I notice some discussion about the Cauchy stress tensor, whether it is covariant or contravariant.  Well, a tensor is neither covariant nor contravariant, while it can be expressed by its covariant, contravariant, or mixed *components* with respect to any arbitrary coordinate system. See the attached short explanation.

Call for papers (abstract dealine: 28 Feb, 2009): 

"Advances in smart materials and adaptive structures" symposium to be held at the third international conference on integrity, reliability and failure, IRF2009

July 20-24, 2009 Porto, Portugal  

Sponsored by the Department of Mechanical and Industrial Engineering, University of Toronto 

Please submit abstract by email to Aarash Sofla: sofla (at) mie.utoronto.ca

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