Imperfection Sensitivity of Cylindrical Shells Under Shear Loading

Abstract

AbstractOne of the basic load cases relevant for the design of shell structures is torsion, which can occur exemplary in silos and tanks under seismic actions or even under wind loading. To address the stability problem of cylindrical shells under this load case, the relevant design standard EN 1993‐1‐6 and the European Recommendation ECCS EDR5 provide simple approaches for the buckling design of cylindrical shells. In order to improve the current hand calculation rules given in the above documents, this numerical study attempts to include the imperfection sensitivity of cylindrical shells subjected to uniform torsion.In the present paper, theoretical, numerical, and experimental results from the literature are reviewed, and new systematic computational analyses and evaluations are introduced regarding the imperfection sensitivity of cylindrical shells under shear loading. For this purpose, a comprehensive computational study was performed using linear and nonlinear buckling analyses on perfect and imperfect shells. Since the influence of imperfections on the buckling strength of cylindrical shells is highly dependent on the imperfection pattern used in the numerical models, nonlinear buckling analyses were performed on imperfect cylindrical shells with three imperfection types: (i) eigenmode‐affine shape from torsion, (ii) longitudinal eigenmode‐affine pattern, and (iii) eigenmode‐affine shape from external pressure.