Detecting precaution, prediction, and early warning for surface landslides

2022 Fiscal Year Final Research Report

• Project/Area Number: 20H02239
• 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: Saitama University
• Principal Investigator: Uchimura Taro 埼玉大学, 理工学研究科, 教授 (60292885)
• Project Period (FY): 2020-04-01 – 2023-03-31
• Keywords: 斜面防災 / モニタリング / 早期警報 / 崩壊予測 / 不飽和土

Outline of Final Research Achievements

This research aims at 1) detection of precautions for slope failure under heavy rainfall considering its mechanism, and 2) use of elastic wave through slope ground to monitor the behavior of slope. Model tests are conducted using a multi-layered shear box, etc., and infiltration of rainwater and resulting shear deformation was observed. Concept of understanding the monitored data onsite is discussed. Changes in propagation properties of elastic wave through the model were also observed during their prefailure process. A slope failure test was also conducted on a real slope on site, and prefailure small displacement and changes of elastic wave velocity were observed. In addition, triaxial tests were conducted to understand the shear strength of unsaturated soils, specially related to its conditions for compaction.

Free Research Field

地盤工学

Academic Significance and Societal Importance of the Research Achievements

豪雨による斜面災害に対する予兆検知と早期警報は、近年のセンサー、無線、情報の技術の急速な発達もあり、重要な防災手法になっている。本研究は、模型と実斜面で斜面表層に雨水が浸透し変形し崩壊する過程を観察した。また、より安価で合理的に斜面の異常を検知する方法として、斜面地盤内の弾性波伝播の変化を監視する方法を検討した。実斜面で人工的に崩壊を起こす実験での観測も試みており、貴重な研究機会となった。これらをもとに、崩壊前に観測される現象の特徴と、それを予兆検知に活かす方法について考察した。