Imperfection sensitivity in the buckling of single curvature concrete shells

Depending on their geometry, supports, material and loads configuration, shells can experience a reduction in the buckling load. If this happens, the shell is said to be sensitive to imperfections. Several approximate methods contemplate the phenomenon of instability in concrete shells, above all that which is based on the IASS Recommendations. In the latter there are some curves reflecting the influence of the initial geometric imperfections in the buckling load for simple geometric models, such as the sphere and the cylinder. In recent decades, different revisions of the Recommendations have been carried out referring to the way the value of the imperfections is quantified. However, new curves, which reflect the influence of imperfections in models with different geometries to those mentioned above, have not been stated. In this study, a method similar to that used by Dulacska and Kollar [1, 5] is implemented to determine the imperfection sensitivity factor in the case of shells with geometries such as a spherical dome and barrel vault.