An improved three-node hybrid-mixed element for Mindlin/Reissner plates

Based on the mixed shear projected (MiSP) approach [6], an enhanced bending approximation for homogeneous isotropic plates is presented. Some hard ben chmark tests, as skew plate (30 degrees) problem for instance, have often s hown poor convergence when low order elements (3- or 4-node element) are de veloped using linear approximations for kinematic variables. To put right t his weakness, we propose a high-order interpolation for rotational dofs whi ch results in more rich bending curvatures. The mid-side rotational nodes a re eliminated using a combination of local discrete kinematic and constitut ive Mindlin hypothesises. The derived 3-node triangular element, called MiS P3+, is free of shear locking and passes all patch-tests for thick and thin plates in an arbitrary mesh. Copyright (C) 2001 John Wiley & Sons, Ltd.