GEOMETRICALLY NONLINEAR-ANALYSIS OF CYLINDRICAL-SHELLS USING SURFACE-PARALLEL QUADRATIC ELEMENTS

A moderately thick cylindrical shell isoparametric element that is cap able of accurately modeling cylindrically curved geometry, while also incorporating appropriate through-thickness kinematic relations is dev eloped. The analysis accounts for fully nonlinear kinematic relations so that stable equilibrium paths in the advanced nonlinear regime can be accurately predicted. The present nonlinear finite element solution methodology is based on the hypothesis of linear displacement distrib ution through thickness (LDT) and the total Lagrangian formulation. A curvilinear side 16-node element with eight nodes on each of the top a nd bottom surfaces of a cylindrical shell has been implemented to mode l the transverse shear/normal deformation behavior represented by the LDT. The BFGS iterative scheme is used to solve the resulting nonlinea r equations. A thin-shallow clamped cylindrical panel is investigated to test the convergence of the present element, and also to compare th e special case of the present solution based on the KNSA (von Karman s train approximation) with those computed using the available faceted e lements, discrete Kirchhoff constraint theory (DKT) and classical shal low shell finite elements, spanning the entire computed equilibrium pa th. Copyright (C) 1996 Published by Elsevier Science Ltd.