Force fluctuations in sheared granular disks

Abstract

The internal structure established within granular materials, often observed as force chains, is dominant in controlling bulk mechanical properties. We designed a two-dimensional Hele-Shaw cell to contain photoelastic disks, and two servos were used on the top and right boundaries individually. We experimentally monitored the fluctuations in force on the top plate while slowing the shearing of the well-confined disks and keeping the right boundary at a contact-confined force of 0.2 kN. The particle rearrangements were found to correspond to bulk force drops and were observed in a localized zone with a length of approximately 5 particle diameters. These results help reveal the structure and mechanics of granular materials, and further investigations are ongoing.

Keywords

granular matter / force chain / stick and slip

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Higher Education Press and Springer-Verlag Berlin Heidelberg