文档介绍：Thin-Walled Structures 42 (2004) 369–397
ate/tws
Effects of imperfections of the buckling
response posite shells
Mark W. Hilburger Ã, James H. Starnes Jr.
NASA Langley Research Center, MS 190, Hampton, VA 23681-2199, USA
Received 9 June 2003; received in revised form 8 August 2003; accepted 11 September 2003
Abstract
The results of an experimental and analytical study of the effects of initial imperfections
on the buckling response and failure of unstiffened thin-pression-loaded graphite-
epoxy cylindrical shells are presented. The shells considered in the study have six different
shell-wall laminates two different shell-radius-to-thickness ratios. The shell-wall laminates
include four different orthotropic laminates and two different quasi-isotropic laminates. The
shell-radius-to-thickness ratios includes shell-radius-to-thickness ratios equal to 100 and 200.
The numerical results include the effects of traditional and nontraditional initial imperfec-
tions and selected shell parameter uncertainties. The traditional imperfections include the
geometric shell-wall mid-surface imperfections that monly discussed in the literature
on thin shell buckling. The nontraditional imperfections include shell-wall thickness varia-
tions, local shell-wall ply-gaps associated with the fabrication process, shell-end geometric
imperfections, nonuniform applied end loads, and variations in the boundary conditions
including the effects of elastic boundary conditions. The cylinder parameter uncertainties
considered include uncertainties in geometric imperfection measurements, lamina fiber
volume fraction, fiber and matrix properties, boundary conditions, and applied end load
distribution. Results that include the effects of these traditional and nontraditional imperfec-
tions and uncertainties on the nonlinear response characteristics, buckling loads and failure
of the shells are presented. The analysis procedure includes a nonlinear static analysis that
predicts t