Postbuckling behavior of pressurized circular cylindrical shells under torsion—I. Experiment

Abstract

Detailed experimental studies are carried out on the postbuckling behavior of clamped circular cylindrical shells under torsion, taking the effect of external or internal hydrostatic pressure into consideration. Polyester test cylinders with radius R=100mm, thickness h=0.25mm and six different lengths L ranging from 22.7 to 161 mm are used and the conections of the angle of twist, axial edge shortening, maximum inward and outward deflections with applied torque are determined under various hydrostatic pressures p, ranging from the external pressure of 0.8 p c to the internal pressure of −1.0 p c (or − 10 p c ), where p c is the critical external pressure. Contour line representations for the typical postbuckling configurations are also obtained. Finally, variations of the critical torque and the wave number with applied pressure are examined to compare favourably with those theoretically predicted.