The Dynamics of the Onset of Frictional Slip

Abstract

Slip Sliding Away The initiation of frictional motion, or slip, along ideal surfaces typically behaves as predicted by rupture models. When stress heterogeneities—similar to irregularities in fault zones in Earth's crust—are introduced, rupture propagation speeds are not as well constrained by models. To improve understanding of slip behavior, Ben-David et al. (p. 211 ; see the Perspective by Zapperi ) measured rupture speeds and stress profiles along an extended frictional interface between two polymer blocks. The experiments revealed a slow mode of slip that occurs when the local ratio of shear to normal stress is sufficiently low. The selection and arrest of three distinct modes of rupture depended on the value of the local stress ratio.