The role of viscoelasticity on heterogeneous stress fields at frictional interfaces

Abstract

a b s t r a c tWe investigate the evolution of heterogeneous stress states along frictional interfaces. Using finite-element simulations, we model the occurrence of precursory slip sequences on a deformable-deformable as well as a deformable-rigid interface between two solids. Every interface rupture creates a stress concentration at its arrest position and erases the stress concentrations produced by previous slip events. While the interface is sticking perfectly between two slip events, erased stress concentrations reappear and survive several cycles of ruptures. Such reestablished stress concentrations are smaller than they were before the rupture. We show that the decrease rate of these stress concentrations is exponential with respect to the number of subsequent events and that the bulk viscoelasticity is at the origin of this history effect. During a slip event, the friction tractions at the interface change almost instantaneously, which leads, between two ruptures, to a relaxation-resembling viscous effect that restores the stress concentration. We describe the decrease rate analytically and highlight that it is proportional to the ratio of the viscous over the instantaneous Young's moduli, and illustrate it by varying the material properties in our simulations.

Linear Elastic Fracture Mechanics Predicts the Propagation Distance of Frictional Slip

“…After the current rupture, they are erased due to the linear slip-weakening friction law [see τ + r ] and will partially reappear over time. This effect was shown to be the result of the bulk's viscoelasticity [22,23].…”

Investigation and modelling of damping mechanisms of magnetorheological elastomers

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Length scale of interface heterogeneities selects propagation mechanism of frictional slip fronts

“…In a detailed study of the transition from sub-Rayleigh to inter-sonic propagation at a onedimensional interface, Liu and Lapusta (2008) demonstrated that a single favorable heterogeneity leads to a secondary crack which accelerates to inter-sonic speeds with an abrupt jump from the Rayleigh wave speed to an inter-sonic speed. The emergence and evolution of increased pre-stress heterogeneities due to the arrest of preceding slip fronts was studied by Radiguet et al (2013Radiguet et al ( , 2015.…”