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arXiv · 0810.0950

Interfacial separation between elastic solids with randomly rough surfaces: comparison of experiment with theory

B. Lorenz·B. N. J. Persson
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Abstract

We study the average separation between an elastic solid and a hard solid with a nominal flat but randomly rough surface, as a function of the squeezing pressure. We present experimental results for a silicon rubber (PDMS) block with a flat surface squeezed against an asphalt road surface. The theory shows that an effective repulse pressure act between the surfaces of the form p proportional to exp(-u/u0), where u is the average separation between the surfaces and u0 a constant of order the root-mean-square roughness, in good agreement with the experimental results.

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B. Lorenz, B. N. J. Persson. 2008-10-06. Interfacial separation between elastic solids with randomly rough surfaces: comparison of experiment with theory. https://doi.org/10.1088/0953-8984%2F21%2F1%2F015003

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