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Curvature condensation and bifurcation in an elastic shell

Moumita Das·Ashkan Vaziri·Arshad Kudrolli·L. Mahadevan
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Abstract

We study the formation and evolution of localized geometrical defects in an indented cylindrical elastic shell using a combination of experiment and numerical simulation. We find that as a symmetric localized indentation on a semi-cylindrical shell increases, there is a transition from a global mode of deformation to a localized one which leads to the condensation of curvature along a symmetric parabolic crease. This process introduces a soft mode in the system, converting a load-bearing structure into a hinged, kinematic mechanism. Further indentation leads to twinning wherein the parabolic crease bifurcates into two creases that move apart on either side of the line of symmetry. A qualitative theory captures the main features of the phenomena and leads to sharper questions about the nucleation of these defects.

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Moumita Das, Ashkan Vaziri, Arshad Kudrolli, L. Mahadevan. 2006-07-26. Curvature condensation and bifurcation in an elastic shell. https://doi.org/10.1103/physrevlett.98.014301

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