Abstract: This paper presents the standard parametric representation of the Tsai-Hill yield criterion in a state of plane stress and the equations governing the stress distribution in a cylindrically orthotropic composite lamina with a circular hole under uniform pressure for the three cases: (a) elastic state,(b) limit state and (c) elastoplastic state. The formulas for the yield pressure and the limit pressure have been obtained.

Key words: nonholonomic system, phase space, analytic mechanics, variable mass, Lie symmetry, conserved quantity