Geotechnical investigation of possible outbreak mechanism on debris flows in Hofu, Yamaguchi in 2009

2014 Fiscal Year Final Research Report

• Project/Area Number: 22360187
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Research Field: Geotechnical engineering
• Research Institution: Yamaguchi University
• Principal Investigator: NAKATA Yukio 山口大学, 理工学研究科, 教授 (90274183)
• Co-Investigator(Kenkyū-buntansha): HYOUDOU Masayuki 山口大学, 理工学研究科, 教授 (40130091) ; SUZUKI Motoyuki 山口大学, 理工学研究科, 准教授 (00304494) ; YOSHIMOTO Norimasa 山口大学, 理工学研究科, 助教 (00325242)
• Project Period (FY): 2010-04-01 – 2015-03-31
• Keywords: 土石流 / まさ土

Outline of Final Research Achievements

The debris disaster occurred in Hofu city, Yamaguchi in July, 2009. The surface geology of the area which occurred was covered mainly with a granite. So, the explication of the debris flow generating mechanism of decomposed granite soil was needed for future disaster prevention and reduction.
Therefore a series of research works were carried out. The following things were understood. (1) It was thought that the cause of large-scale debris flow had not only the rise of the groundwater level by rain water but inflow of groundwater from the stratum. (2) The geographical feature inflowing groundwater was presumed to be a place characterized by lineament. (3) At such a place, the higher level of the groundwater continued over the long period of time in rain and after rain.

Free Research Field

地盤工学