Direct observation of frictional contacts during high-velocity slip

2017 Fiscal Year Final Research Report

• Project/Area Number: 16K13877
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Solid earth and planetary physics
• Research Institution: Japan Agency for Marine-Earth Science and Technology
• Principal Investigator: KUWANO Osamu 国立研究開発法人海洋研究開発機構, 数理科学・先端技術研究分野, 研究員 (30511969)
• Project Period (FY): 2016-04-01 – 2018-03-31
• Keywords: 高速摩擦 / 閃光発熱 / 可視化 / 真実接触点

Outline of Final Research Achievements

Recent experiments conducted at sub-seismic to seismic sliding velocities (mm/s to ms) show the dramatic weakening in the friction coefficient for a wide variety of rock types due to mechanochemical effects by frictional heating. Consequently, several weakening mechanisms have been proposed depending on the type of rock specimens. Some of them are based on the sample observation and analysis after experiments. Direct observation of frictional contacts during an experiment is indisputable to constrain an elementary process at frictional contacts during slip. We developed experimental system for direct observation of frictional contacts during high velocity sliding experiment. We observed flash lightning at frictional contacts during high-velocity slip. We successfully measured the temperature distribution of microscopic contacts using two-color method.

Free Research Field

実験地震物理学