Hitting the mark: probing at the initiation site allows for accurate prediction of a thin shell’s buckling load

Abstract

Geometric imperfections are understood to play an essential part in the buckling of a thin shell, but how multiple defects interact to control the onset of failure remains unclear. Here, we examine the failure of real cylindrical shells by experimentally poking soda cans with a large imparted dimple. By high-speed imaging of the can’s surface, the initiation of buckling from axial loading is directly observed, revealing that larger dimples tend to set the initial buckling location. However, the influence of the shell’s background geometric imperfections can still occasionally dominate, causing initiation to occur far from the dimple. In this situation, probing at the dimple leads to an over-prediction of the axial capacity. Using finite-element simulations, we understand our experimental results as a competition between the large dimple and the shell’s inherent defect structure. In our simulations, we empirically observe a deformation-based criterion that connects the ideal poking location to the initiation site. This article is part of the theme issue ‘Probing and dynamics of shock sensitive shells’.

Experimental studies on snaking in 3D-printed cylindrical shells under axial compression using photogrammetry

“…Virot et al [29] traced experimentally a 3D stability landscape of the shells using a poking methodology and demonstrated the minimum energy barrier path for cylindrical buckling. The experimental and numerical studies of Cuccia et al [30] emphasized the significance of poking location on the viability of the ridge tracking procedure in the stability landscape for accurate buckling load predictions.…”

“…The experimental and numerical studies of Cuccia et al. [30] emphasized the significance of poking location on the viability of the ridge tracking procedure in the stability landscape for accurate buckling load predictions.…”

Foreword to the special issue on new developments in structural stability

“…The papers by Cuccia et al [ 7 ] and Groh et al . [ 8 ] deal with application of the probing technique to cylindrical shells under axial compression.…”

“…The papers by Cuccia et al [7] and Groh et al [8] deal with application of the probing technique to cylindrical shells under axial compression. The first paper examines the elastic buckling of thin shell soda cans that have been deliberately dented.…”