Entropic rigidity of a crumpling network in a randomly folded thin sheet

TL;DR

This paper investigates the entropic rigidity of crumpling networks in randomly folded sheets, combining experiments and theory to reveal how network entropy influences mechanical response and scales with density.

Contribution

It introduces a theoretical force-compression model based on network entropy and demonstrates universal scaling of rigidity with density in crumpled sheets.

Findings

Force-compression relationship fits experimental data well.

Entropic rigidity modulus scales as a power of mass density.

Network entropy governs the mechanical behavior of crumpled sheets.

Abstract

We have studied experimentally and theoretically the response of randomly folded hyperelastic and elastoplastic sheets on the uniaxial compression loading and the statistical properties of crumpling networks. The results of these studies reveal that the mechanical behavior of randomly folded sheets in the one-dimensional stress state is governed by the shape dependence of the crumpling network entropy. Following up on the original ideas by Edwards for granular materials, we derive an explicit force-compression relationship which precisely fits the experimental data for randomly folded matter. Experimental data also indicate that the entropic rigidity modulus scales as the power of the mass density of the folded ball with universal scaling exponent.