2023 Fiscal Year Final Research Report

Development of a geo-disaster reduction technique by using timber piles to add value to B and C grade logs

Research Project

PDF

Project/Area Number	21K05698
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Multi-year Fund
Section	一般
Review Section	Basic Section 40010:Forest science-related
Research Institution	Tobishima Research Institute of Technology
Principal Investigator	Murata Takumi 飛島建設株式会社技術研究所, －, 研究員 (40829959)
Co-Investigator(Kenkyū-buntansha)	沼田淳紀飛島建設株式会社技術研究所, －, 主席研究員 (10443649) 北原文章国立研究開発法人森林研究・整備機構, 森林総合研究所, 主任研究員等 (50582748) 宮島昌克金沢大学, 地球社会基盤学系, 教授 (70143881)
Project Period (FY)	2021-04-01 – 2024-03-31
Keywords	丸太 / B材．C材 / 液状化 / 地盤補強
Outline of Final Research Achievements	The purpose of this study is to elucidate the geotechnical properties of B and C grade logs and to verify their applicability to geo-disaster reduction technique such as liquefaction countermeasures and ground reinforcement. In this study, vertical displacement characteristics of the ground due to log insertion into the ground, vertical bearing capacity characteristics of knotted and joined logs, and factors affecting the taper rate of logs were clarified by model experiments, field experiments, and date analysis. Furthermore, based on these results, the applicability of B and C grade logs to geo-disaster reduction technique was verified and specific application methods were shown. In addition, the applicability of B and C grade logs of medium and large diameter, which is expected to increase in the future, to geo-disaster reduction technique was verified based on an overseas case study.
Free Research Field	地盤工学
Academic Significance and Societal Importance of the Research Achievements	本研究の成果により，B材およびC材を地盤災害軽減技術に活用できることが明らかとなった．これにより，B材およびC材の新たな市場の開拓と，それに伴うこれら木材の価値向上が期待される．また，森林所有者に還元される利益が多くなるため，再造林とそれに伴う持続可能な森林経営の促進が見込まれる．さらに，地盤災害軽減技術として使用するB材およびC材は，生物劣化の心配がない地下水位以深の地中に打設されるため，これらの木材に固定された炭素は半永久的に地中に固定される．このように，本研究の成果により，持続可能な森林経営の促進と気候変動緩和への貢献が期待される．