Development of a novel geo-biotechnology for silicate fixation

2023 Fiscal Year Final Research Report

• Project/Area Number: 21K18754
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 22:Civil engineering and related fields
• Research Institution: University of the Ryukyus
• Principal Investigator: Matsubara Hitoshi 琉球大学, 工学部, 教授 (50414537)
• Project Period (FY): 2021-07-09 – 2024-03-31
• Keywords: 珪酸塩 / ジオバイオテクノロジー / MISP / 自己修復 / 地盤修復

Outline of Final Research Achievements

This study aimed to pioneer a geobiotechnology called MISP (Microbially Induced Silicate Precipitation) technology. Envisioned as an advanced method for rock restoration, it is expected to boast exceptional durability and resilience against the effects of aging.　Field investigations revealed that microorganisms are deeply involved in the formation of silicate minerals observed on Aguni Island, and it was found that their internal annular structures are reinforced with microbially induced calcium carbonate. Furthermore, it was found that silicate minerals could be artificially precipitated by employing microorganisms isolated and cultured from the island outcrops. These findings greatly expand the potential for advancing next-generation ground improvement technologies.

Free Research Field

地盤工学，地圏工学

Academic Significance and Societal Importance of the Research Achievements

微生物を用いた地盤修復技術は炭酸塩の析出技術に拠るところが大きく，最近になって脱窒細菌によって飽和砂地盤を不飽和化する技術が提案されたに過ぎない。このような状況下において，実環境に存する珪酸塩鉱物の微細構造や生成と微生物の関連性を明らかにし，現地露頭から分離培養した微生物を用いて珪酸塩鉱物の析出を人工的に誘導した例は本研究以外に見当たらない。これらの成果は，微生物を用いた地盤改良技術に関する知見を大きく広げるものであり，学術的な意義は極めて大きい。また，本技術は最終的には地盤災害の軽減化を目指すものであるため，防災の観点からも社会的に重要な意義を持つ。