Precursors of Global Slip in a Longitudinal Line Contact Under Non-Uniform Normal Loading

Abstract

This article describes the mechanism of precursor events; the mechanism was determined through an experiment and simulation by considering non-uniform normal loading. In the experiment, real-time observations of a contact zone were performed using a longitudinal line contact of PMMA specimens (i.e., a slider on a stationary base block) under a total normal load of 400 N. Partial propagations of the detachment front were considered as precursor events, and it was found that non-uniform normal loading influences the occurrence frequency of the precursor events and the increasing rate of the propagation length. In the simulation, the time evolution of a multidegree-of-freedom system with Coulomb friction was studied. The model considered in the simulation comprised multiple masses serially connected by linear springs on a stationary rigid plane. By regarding the precursor in the experiment to correspond to a partial slip (i.e., simultaneous slip of some of the masses) in the simulation, the influence of non-uniform normal loading on the precursor events can be explained to a certain extent. Additionally, it was found that the apparent static friction coefficient (i.e., the ratio of the maximum tangential load to the total normal load) could be lesser than the real static friction coefficient due to the residual strain in the slider.

Recent developments in dynamic fracture: some perspectives

“…Once the loading configuration was changed, the measured value of µ s for the same two blocks could be varied significantly and controllably. This surprising result has been confirmed in recent theoretical and numerical studies [158][159][160][161]. In addition to analytical work, recent numerical work [158,159,162,163] together with simple models describing the contact dynamics of ensembles of discrete contacts have been successful in describing many aspects of frictional cracks [148,[164][165][166][167].…”

Static and dynamic friction of hierarchical surfaces

“…This model was first introduced by Burridge and Knopoff [22] in the study of the elastic deformation of tectonic plates. Despite its simplicity, the model is still used not only in this field [23][24][25], but also to investigate some aspects of dry friction on elastic surfaces, e.g., the static to dynamic friction transition [26][27][28][29][30], stick-slip behavior [31][32][33], and the role of regular patterning [34].…”

Probing the micromechanics of a multi-contact interface at the onset of frictional sliding

“…In the past ten years, several experimental groups developed new optical methods to obtain spatially resolved mechanical measurements [4,5,6,7,8], which triggered intense subsequent theoretical and numerical investigations [9,10,11,12,13,14,15]. Fineberg and collaborators studied the onset of sliding of a multi-contact interface, in a planeplane contact configuration, submitted to an adiabatic tangential loading [6,7].…”