5-node hybrid/mixed finite element for Reissner-Mindlin plate

In this paper, a new quadrilateral 5-node plate bending element (HP5) for h ybrid/mixed finite element method is presented in the global Cartesian coor dinates by the Hellinger-Reissner functional. This new element is based on the independent interpolations for displacement and stress. Its convergence is proven by theory and through detailed numerical investigations. The num erical studies demonstrate the validity of the resulting new element HP5 an d show that the present element possesses many ideal qualities, i.e. remark able convergence for thin and thick plates, a lower sensitivity to geometri c distortion and invariability to the rotation of coordinates, freedom of s hear locking phenomenon in the thin plate limit, suppression of spurious ze ro energy deformation modes, and the accuracy of solution is improved over that of 4-node hybrid/mixed finite element (HP4). Very good results have be en obtained for thin and thick plates and show that it is a satisfactory fo undation of developing h-version and p-version adaptive hybrid/mixed finite element method. (C) 1999 Elsevier Science B.V. All rights reserved.