Biswajit Banerjee's blog

I've mostly had quite helpful responses from iMechanica participants whenever I've asked questions on this forum.  However, I've noticed that questions from several posters have gone unanswered.  I feel that there are two main reasons for that lack of response:

1) The questioner has not provided an adequate details by which they can be identified.  I generally don't like responding to a question posed by someone called xyz1983. 

I was browsing the discussion page for Stress in Wikipedia when I came upon this interesting comment:

"

Refutation of Cauchy stress

The theory of stress based on Euler & Cauchy is now refuted. The profound incompatibility of this theory with the rest of physics, especially the theory of potentials and the theory of thermodynamics, has been documented in

Here's a puzzle for our readers.  The following image is of the surface of a failed joint followed by a picture of the joint (not the same one but a similar one) before joining.  What material is it? What caused the failure?  All manner of speculation is welcome.

Failed joint

Unfailed joint

Modern composite structures have a wide spread in their failure stress.  Advanced multiphysics codes can have a wide range of predicted behavior for nominally the same inputs.  How do we certify the design of such structures or the accuracy of such codes?

A few weeks ago I had mentioned in one of my comments that

I'm leaving the US in a couple of days and will probably take a hiatus of a few months from iMechanica.  Before I leave, I want to tell you about a C++ idiom that eases the implementation and use of multiple material models in a computational mechanics code.

I had promised to talk about subversion in my post on digitizing and editing figures but never quite got around to it. A recent spate of requests about downloading Uintah reminded me of my promise. So here's the story.