On parametric minimum complementary energy variational principle in soil mechanics

The parametric minimum complementary energy variational principle is given in this paper. To the problems of nonassociative flow rule in the theory of plasticity, the Drucker postulation can no longer be applied and the classical variational principles fail, the parametric variation principles can play the role instead. The parametric variational principle can be used for the finite element solution with sequential quadratic programming method to soil mechanics problems.