Crumpled Kirigami

Crushing a paper into an approximately spherical shape will create a crumpled ball made up of complex structural features such as long-range structures (folds, bends, and ridges) as well as short-range structures (D-cones). One of the most surprising things about crumpled matter is its high rigidity and light weight. Previous studies have suggested different origins of the stiffness through models based on the dominance of different structural features. In this study, we attempt to experimentally narrow down possible origins by topologically impairing long range structures in the sheet. Simple experiments using two parallel walls, a force sensor and a confocal microscope for observation, show that ‘topologically impaired’ sheets have compressive behavior which is indistinguishable from pristine sheets. We discuss several materials but are forced to conclude that short range structures (d-cones) must dominate long range structures (bends, folds or ridges).