A framework for nonlinear shells based on generalized stress and strain measures

very general class of shell theories is established, based on a unified variational principle and on expansions with respect to biorthogonal function systems. The shell models derived are able to accommodate the flow theory of large strain thermoelastoplasticity including the effects due to unloading. The specific case of a compressible neo-Hookean material with a von Mises yield condition is discussed in detail. 0 1997 Elsevier Science Ltd.