BEGIN:VCALENDAR VERSION:2.0 PRODID:-//Talks.cam//talks.cam.ac.uk// X-WR-CALNAME:Talks.cam BEGIN:VEVENT SUMMARY:Cracks in ice and their role in brittle compressive failure - Erla nd Schulson (Dartmouth College) DTSTART:20171207T113000Z DTEND:20171207T123000Z UID:TALK96334@talks.cam.ac.uk CONTACT:INI IT DESCRIPTION:Cracks--new and old\, short and long-- are ubiquitous fe atures within the arctic sea ice cover. How they form and the role they pl ay in mechanical behavior are important questions in ice mechanics. In thi s presentation\, emphasis will be placed on brittle compressive failure. T here\, cracks preferentially oriented with respect to the applied stress s tate can slide intermittently across opposing surfaces in contact\, activa ting in the process deformation mechanisms that can account for a number o f observations/characteristics of brittle compressive failure on scales sm all and large. One such scale-independent mechanism is the wing-crack cum comb-crack mechanism: it can account for the axial splitting and shear fau lting modes of terminal failure\, conjugate faulting\, brittle compressive strength and\, upon consideration of crack-tip creep\, the transition fro m brittle to ductile behavior. Application of confining stress above a cri tical level\, set solely by the coefficient of kinetic friction\, suppress es frictional sliding and activates\, given a sufficiently high strain rat e and triaxial confinement\, a brittle-like mode of plastic failure govern ed by the different mechanism of adiabatic heating and dynamic recrystalli zation. These mechanisms will be described and questions arising addressed .

 LOCATION:Seminar Room 1\, Newton Institute END:VEVENT END:VCALENDAR