Elucidation of gully erosion characteristics considering the periodicity of unevenness on embankment crest

2021 Fiscal Year Final Research Report

• Project/Area Number: 19K04611
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Review Section: Basic Section 22040:Hydroengineering-related
• Research Institution: Saitama University
• Principal Investigator: Yagisawa Junji 埼玉大学, 理工学研究科, 准教授 (70549998)
• Project Period (FY): 2019-04-01 – 2022-03-31
• Keywords: 河川堤防 / 越流 / ガリー侵食 / 堤防天端の凹凸の周期性

Outline of Final Research Achievements

The purpose of this study is to clarify the high-risk points leading to the levee breakage at an early stage, considering the overflow water depth, the periodicity of the longitudinal unevenness of the top of the levee, and the difference in the back slope.
As a result of experiments and numerical analysis, it was clarified that there is a peak uneven wavelength in which the scale of gully erosion (erosion depth) and the distance between adjacent gully are shortened even if the overflow conditions are the same.
This suggests that it is useful to grasp the weak points where the risk of early levee breakage is high by grasping the wavelength of the top unevenness at the points where the risk of overflow is high.

Free Research Field

水工水理学

Academic Significance and Societal Importance of the Research Achievements

従来堤防越流を伴う侵食に関する研究は，堤防形状を理想化した状態での評価に留まる研究が多い．本研究では，堤防天端に生じる縦断的な凹凸を考慮した上で，生じるガリー侵食の特性を把握できるため，その学術的意義は高い．本研究で得られた知見は，現存する堤防の越流危険箇所に対して天端の凹凸の状況を把握することで，堤防天端の効率的な補修計画に大きく貢献できると期待され，本研究の工学的，社会的意義は非常に高い．