Cause Investigation and Mitigation Method for Long Distance Fluidized Flow in Gently Sloped Soils during Inland Earthquake

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H02244
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 22030:Geotechnical engineering-related
• Research Institution: Kyushu University
• Principal Investigator: Hazarika Hemanta 九州大学, 工学研究院, 教授 (00311043)
• Co-Investigator(Kenkyū-buntansha): Rohit Divyesh・Mohanbhai 九州大学, 工学研究院, 学術研究員 (30944508) ; 飛田 哲男 関西大学, 環境都市工学部, 教授 (00346058) ; 岡村 未対 愛媛大学, 理工学研究科(工学系), 教授 (50251624) ; 清田 隆 東京大学, 生産技術研究所, 准教授 (70431814) ; 兵動 太一 富山県立大学, 工学部, 講師 (80749078)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: Palu震災 / 直下型地震 / 緩傾斜地盤 / 長距離流動 / 液状化 / 水膜現象

Outline of Final Research Achievements

The objectives of this study are: (1) to focus on the long-distance fluidized failure of gently sloped ground in several locations of Palu city caused by the 2018 Central Sulawesi Earthquake (Mw = 7.5), Indonesia, and to determine its causes from both the geological structure and the geotechnical features, and (2) to assess the risk of similar damage caused by earthquakes of similar magnitude in similar regions of the world. Based on data analysis of field investigations, laboratory tests of collected soils, model tests and numerical simulations reproducing the geological structure, the mechanism of vulnerability of gently sloped ground during inland earthquakes was elucidated and methods for evaluating the flow distance was established.

Free Research Field

地盤工学・地盤防災学

Academic Significance and Societal Importance of the Research Achievements

本研究の成果により、同規模の地震を想定して、我が国で類似の地質構造を有する地域のハザードマップを作成することが可能となり、その地震防災対策の策定およびレジリエントな街づくりに大きく貢献できる。また、大地震時における社会基盤施設の安定性向上について新たな指針を与えることに、本研究は豊富な社会的意義を有している。