BEGIN:VCALENDAR
VERSION:2.0
PRODID:-//Memento EPFL//
BEGIN:VEVENT
SUMMARY:Friction is Fracture: Fracture Processes Drive Frictional Motion
DTSTART:20140124T110000
DTEND:20140124T120000
DTSTAMP:20260916T061342Z
UID:4d7b157c02997dd68e3baed8c0fa49314c4e5461b3508821d8f103af
CATEGORIES:Conferences - Seminars
DESCRIPTION:Prof. Jay Fineberg\nBio: Jay is interested in many different (
 rather loosely related  topics) whose main common denominator is that the
 y are nonlinear phenomena\, that he would like to understand.\nFrictional 
 processes entail the rupture of the ensemble of discrete contacts defining
  a frictional interface. There are a variety of views on how to best descr
 ibe the onset of dry frictional motion. These range from modeling friction
  with a single degree of freedom\, a “friction coefficient”\, to theor
 etical treatments  employing dynamic fracture to account for spatial and 
 temporal dynamics along the interface. We perform simultaneous high-speed 
 measurements of the real contact area and the strain fields in the region 
 surrounding propagating rupture tips.  We show that\, along dry (nominall
 y flat) rough interfaces\, the transition from "static" to "dynamic" frict
 ion is quantitatively described by classical singular solutions for the mo
 tion of a rapid shear crack. We find that these singular solutions\, origi
 nally derived to describe brittle fracture\, are in excellent agreement wi
 th the experiments for slow propagation while some significant discrepanci
 es arise as the rupture velocity\, Cf\, approaches the Rayleigh wave speed
 \, Cr. In addition\, the energy dissipated in the fracture of the contacts
  remains nearly constant throughout the entire range of "Cf less than Cr"\
 , while the size of the dissipative zone undergoes a Lorentz-like contract
 ion as Cf approaches Cr. This coupling between friction and fracture is cr
 itical to our fundamental understanding of frictional motion and related p
 rocesses\, such as earthquake dynamics.
LOCATION:GC C3 30 http://plan.epfl.ch/?zoom=20&recenter_y=5864175.11538&re
 center_x=731009.66423&layerNodes=fonds\,batiments\,labels\,information\,pa
 rkings_publics\,arrets_metro\,transports_publics&floor=3&q=GCA_330
STATUS:CONFIRMED
END:VEVENT
END:VCALENDAR