Non-monotonic dynamics in the onset of frictional slip

Kasra Farain; Daniel Bonn

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arXiv · 2107.02723

Non-monotonic dynamics in the onset of frictional slip

Kasra Farain·Daniel Bonn

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Abstract

The transition from static to dynamic friction is often described as a fracture-like instantaneous slip. However, studies on slow sliding processes aimed at understanding frictional instabilities and earthquakes report slow friction transients that are usually explained by empirical rate-and-state formulations. We perform very slow ($\sim nm/s$) macroscopic-scale sliding experiments and show that the onset of frictional slip is governed by continuous non-monotonic dynamics originating from a competition between contact aging and shear-induced rejuvenation. This allows to describe both our non-monotonic dynamics and the simpler rate-and-state transients with a single evolution equation.

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Kasra Farain, Daniel Bonn. 2021-07-06. Non-monotonic dynamics in the onset of frictional slip. https://arxiv.org/abs/2107.02723

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