Frictional dynamics of viscoelastic solids driven on a rough surface

TL;DR

This paper investigates how viscoelastic properties influence the frictional behavior of a spring-block model on rough surfaces, revealing velocity-dependent regimes and supporting phenomenological rate-and-state friction laws.

Contribution

It provides a microscopic basis for rate-and-state friction models by analyzing viscoelastic effects in a mean field spring-block system.

Findings

At high drive velocities, the system exhibits velocity-weakening friction.

Below a critical velocity, stick-slip motion occurs.

Friction peaks grow with hold time in slide-hold-slide tests.

Abstract

We study the effect of viscoelastic dynamics on the frictional properties of a (mean field) spring-block system pulled on a rough surface by an external drive. When the drive moves at constant velocity V, two dynamical regimes are observed: at fast driving, above a critical threshold Vc, the system slides at the drive velocity and displays a friction force with velocity weakening. Below Vc the steady sliding becomes unstable and a stick-slip regime sets in. In the slide-hold-slide driving protocol, a peak of the friction force appears after the hold time and its amplitude increases with the hold duration. These observations are consistent with the frictional force encoded phenomenologically in the rate-and-state equations. Our model gives a microscopical basis for such macroscopic description.