Identification by modal analysis of composite structures modelled with FSDT and HSDT laminated shell finite elements

This paper presents an improvement and an extension to modal analysis of an existing multilayered composite shell finite element. Generalising the formulation to a set of elements, the proposed models are based upon the first- and higher-order shear deformation theories and are well suited for evaluating the global dynamic response of thin and thick laminated shells respectively. Characterized by a through-the-thickness displacement approximation of a freely chosen order, they display excellent convergence properties when the polynomial order is increased and present a higher computational effectiveness in comparison to the classical layerwise models. The models considered are compared to closed-form solutions based on the layerwise plate theory and the so-called zig-zag formulation. Experimental and numerical modal test cases on thin and thick plates are next investigated in order to validate the proposed shell models. Good agreement is found with the analytical, experimental and numerical references. (C) 2004 Elsevier Ltd. All rights reserved.