Numerical investigation on stability of gravel bags in flooding as flexible riverbank protection works and a new design method

2023 Fiscal Year Final Research Report

• Project/Area Number: 19K04623
• 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: University of the Ryukyus (2020-2023); Chuo University (2019)
• Principal Investigator: Fukuda Tomoo 琉球大学, 工学部, 准教授 (00709694)
• Project Period (FY): 2019-04-01 – 2024-03-31
• Keywords: 袋詰玉石工 / 固液混相流解析 / 構造 / 配置 / 屈撓性 / 河岸保護 / 流体力 / 三次元解析

Outline of Final Research Achievements

A new numerical simulation method was developed that is capable of estimating the interaction between flexible gravel bags and flood flows. The developed numerical method was utilized to simulate a case where gravel bags were washed out away by flood flows. The simulation result reproduced well the phenomenon of gravel bags washout. Furthermore, by utilizing the developed numerical method, effective arrangements and structures for gravel bags were proposed.

Free Research Field

水工学

Academic Significance and Societal Importance of the Research Achievements

袋詰玉石工に作用する水流による流体力や，袋詰玉石間の相互作用力の推定は容易ではなく，袋詰玉石工の流失事例が後を絶たない．本研究では，水流に対して安定しやすい袋詰玉石工の構造と配置を提案した．さらに，袋詰玉石工と水流の相互作用を解析することができるこれまでにない新しい数値解析法開発した．開発した数値解析法の活用により，任意の河岸地形や水流の境界条件に対して，効果的な袋詰玉石工の設計が可能になると考えられる．