Elephant's foot buckling and imperfection sensitivity of internally pressurized thin-walled metal cylinders subjected to bending

Abstract

Upright cylindrical steel storage tanks, subjected to lateral loading, may fail in the form of local buckling near their bottom, due to the simultaneous action of excessive axial compression in the presence of internal pressure, a failure mode known as "elephant's foot buckling". The present paper is aimed at examining this failure mode rigorously, considering material and geometric nonlinearities, accounting for initial imperfections for pressure levels up to 80% of yield pressure. The accuracy of simplified axisymmetric models in modelling this instability mode is also examined. Finally, the numerical results are compared with the predictions from the relevant provisions of EN 1993-1-6 and EN 1998-4. Copyright ©: SDSS'2016.