HP VERSION OF FINITE-ELEMENT MIXED METHOD

Mixed formulation of the hp version of the finite-element method is developed in the case of rotational shells subjected to axisymmetric and asymmetric loads. The circumferential variations of moments and displacements are expressed in terms of Fourier series expansions. Integrals of Legendre polynomials are used as shape functions for approximating the variation of deflections and moment resultants in the meridional direction. The arbitrary meridional curve of the shell is represented by Legendre polynomials. Reissner's variational principle is used in setting up the mixed matrices and vectors. Body residuums and unbalanced nodal fractions are used as error indicators. A number of rotational shell problems with steep stress gradients are considered and the efficacy of using mesh refinements in the hp mode is evaluated.