J-GLOBAL ID:200904028045095925  Research Project code:0450021918 Update date:Nov. 08, 2004

Elucidation of formation process of slip nuclei by means of giant direct shear tester

Study period:2003 - 2005
Organization (1):
Investigating Researcher (1):
Research overview:
In a formation process of a seismic center, it is conceived that quasi-static pre-slip propagates prior to dynamic slip. Getting hold of such movement is inevitable for understanding an earthquake generation mechanism. However, with conventional experiments and earthquake observation means, it is difficult to observe slip vectors and velocity per each asperity unit in a formation process of slip nuclei, thickness and propagation of shearing planes, and particularly, variation of gap-water pressure that is regarded as important in a seismic center area at an ocean trench. Still less, there is no analysis comparing record of movement with deformed structure of substances constituting slip nuclei. A landslide area is ordinarily at a standstill. However, in case of a heavy rainfall, it shows a distinctive feature of repeating stick-and-slip in a short time in a range from several millimeters to tens of centimeters due to increase of gap-water pressure. By observing such movement precisely and dynamically, we investigate the following contents: 1 Movement of asperity in a process from quasi-static slip to dynamic slip and variation of gap-water pressure are elucidated. 2 Thickness and strain of shearing planes of slip nuclei and identity with dynamic slip planes become clear. 3 Core samples are taken from slip nuclei. We integrate results of structure analysis of slip nuclei with results of movement observation. We aim at making a model of friction formation rule for substances causing dynamic slip while occluding gap water.
Project Organization (1):
  • (C013000000)
Research program: Grant-in-Aid for Scientific Research
Ministry with control over the research :
Ministry of Education, Culture, Sports, Science and Technology

Return to Previous Page