Creep buckling with limit point type for viscoelastic laminated circular cylindrical shells under axial compression

Based on the Donnels shell theory, the creep buckling behavior, in the form of limit point, was investigated for viscoelastic laminated circular cylindrical shells under uniformly axial compression with geometrical imperfections. The quasi-elastic approach was applied to the analysis of end-shorting following elapsed time, and the critical time is determined at which the snap-through of end-shorting occurs. The numerical investigation of glass/epoxy laminated circular cylindrical shells was performed. It is shown that there exist durable critical loads which correspond to infinite critical time. The difference between transient critical load and durable critical load, which characterizes the extent of time-dependent buckling, decreases with the increase of imperfection. The mechanism of the influence on the buckling behavior for ply mode, the amplitude of imperfection and boundary conditions as well can be examined by combining the discussion on the sensitivity of imperfection for the corresponding elastic counterpart.