Hybrid-Stress Reduced Mindlin Isoparametric Elements for the Analysis of Thin Plates

Abstract

ABSTRACT Hybrid-stress isoparametric finite elements are developed for the analysis of thin plates utilizing independent interpolations for transverse displacement and cross-section rotations. The formulation is based on earlier hybrid-stress plate elements that utilize Mindlin-type displacement fields and include transverse shear stress and transverse normal stress contributions. By neglecting the contributions of transverse shear and normal stresses to the complementary strain energy, isoparametric thin plate elements are obtained that have the same performance characteristics as the non-reduced element in the thin plate limit. This is illustrated for a two-node beam element. In addition to the ease of formulating isoparametric thin plate elements using C ° displacement interpolations, the primary advantage of this approach over the nonreduced element is the significant savings of computation time for element stiffness generation that is made possible. Computational considerations are illustrated for an 8-node invariant isoparametric plate element.