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Stress and fold localization in thin elastic membranes
Luka Pocivavsek1, Robert Dellsy, Andrew Kern
1Department of Chemistry and James Franck Institute (JFI), University of Chicago, Chicago, IL 60637, USA.
Science (New York, N.Y.)
|May 20, 2008
Summary
Thin elastic membranes develop folds, not just wrinkles, when compressed. This new understanding of membrane mechanics applies to biological and material systems.
Area of Science:
- Materials Science
- Physics
- Biophysics
Background:
- Thin elastic membranes on soft substrates deform under compression.
- Periodic wrinkling is a known deformation mode.
Purpose of the Study:
- To investigate deformation patterns beyond wrinkling in compressed elastic membranes.
- To characterize the transition to folded states and establish scaling laws.
Main Methods:
- Numerical simulations of membrane mechanics.
- Experimental validation using supported membranes.
- Analysis of curvature and wavelength transitions.
Main Results:
- Periodic wrinkling is not the only outcome; folds emerge at higher compression.
- Folds appear when compression exceeds a third of the wrinkle wavelength.
- A symmetry-broken state with flat and folded regions is observed.
Conclusions:
- The study reveals a new deformation mode (folding) in compressed membranes.
- General scaling laws for wrinkled and folded states are provided.
- Findings offer insights into interfacial stability in biological and thin-film systems.
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