Talk:Drucker–Prager yield criterion

Authors
Is "Prager" William Prager? —DIV (128.250.80.15 (talk) 02:47, 19 January 2009 (UTC))
 * Yes. Bbanerje (talk) 03:41, 13 February 2009 (UTC)

Diagrammes
I don't understand the images under Derivation of expressions for A,B in terms of c,φ. They need more explanation somewhere. —DIV (128.250.80.15 (talk) 00:20, 22 January 2009 (UTC))


 * These are just two views of the yield surface (in principal stress space). The figure on the right shows the intersection of the $$\sigma_1-\sigma_2$$ plane with the two yield surfaces.  The figures were generated in Matlab. I'm sure better ones can be created.  Bbanerje (talk) 03:44, 13 February 2009 (UTC)

Expressions in terms of cohesion and friction angle
The expressions for circumscribed, inscribed and middle circumscribed seem to have got mixed up. They do not match the derivation.