APPROXIMATE SOLUTIONS TO THE ORTHOTROPIC PINCHED CYLINDER PROBLEM

The pinched cylinder problem provides a useful and challenging test of shell behaviour, but exact benchmark solutions are limited, in practi ce, to the cases of infinitely-long cylinders and finite cylinders wit h simply-supported ends, and are somewhat tedious to implement. The pr actical need is identified for simpler solutions to the problem for or thotropic cylinders, and suitable solutions are extended from earlier work by Ting, Yuan and Calladine relating to isotropic cylinders. In o rder to obtain the first two of these solutions, orthotropic versions of the simple and complete Donnell equations are presented. A combinat ion of the first two methods gives results in good agreement with refe rence solutions for cylinders with free ends, but variable agreement f or simply-supported cylinders. There are close similarities between th e solutions extended from Ting and Yuan and Calladine, and these are a pplied to a filament-wound tube with varying winding angles and thickn ess. (C) 1998 Elsevier Science Ltd. All rights reserved.