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arXiv · 0912.3778

Mechanical response of a self avoiding membrane: fold collisions and the birth of conical singularities

Paula Mellado·Shengfeng Cheng·Andres Concha
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Abstract

An elastic membrane that is forced to reside in a container smaller than its natural size will deform and, upon further volume reduction, eventually crumple. The crumpled state is characterized by the localization of energy in a complex network of highly deformed crescent-like regions joined by line ridges. Previous studies have focused on the onset of the crumpled state by analyzing the mechanical response and stability of a conical dislocation, while others have simulated the highly packed regime neglecting the importance of the connectivity of the membrane. Here we show, through a combination of experiments, numerical simulations, and analytic approach, that the emergence of new regions of high stretching is a generic outcome when a self avoiding membrane is subject to a severe geometrical constraint. We demonstrate that, at moderate packing fraction, interlayer interactions produce a response equivalent to the one of a thicker membrane that has the shape of the deformed one. Evidence is found that friction plays a key role stabilizing the folded structures.

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Paula Mellado, Shengfeng Cheng, Andres Concha. 2009-12-18. Mechanical response of a self avoiding membrane: fold collisions and the birth of conical singularities. https://doi.org/10.1103/physreve.83.036607

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