Buckling and Postbuckling Studies of Moment-Loaded Thin-Wall Cylindrical Shells with Cutouts

An experimental study of the prebuckling, incipient buckling, and postbuckling behavior of thin-wall aluminum cylindrical shells with a nominal R/h of 100 and subjected to pure bending is reported. The investigation includes initially-undamaged and cutout-predamaged cylindrical shells. The types of predamage include: (a) a single circular hole (three different diameters were employed) and (b) a single slotted hole of fixed size and aspect ratio but oriented axially (phi = 0 degrees), obliquely (phi = 45 degrees), or circumferentially (phi = 90 degrees). Emphasis is given to studying the load-deflection behavior and the associated buckling patterns in the postbuckling range, for both monotonically-increasing angular deflections of the buckled region and unloading-reloading behavior. Load-deflection characteristics and buckling patterns distinctive to each type of specimen tested are presented for bending rotations extending to about 15-20 degrees. (Author)