Project/Area Number |
18H01683
|
Research Category |
Grant-in-Aid for Scientific Research (B)
|
Allocation Type | Single-year Grants |
Section | 一般 |
Review Section |
Basic Section 25030:Disaster prevention engineering-related
|
Research Institution | Kyushu University |
Principal Investigator |
|
Project Period (FY) |
2018-04-01 – 2021-03-31
|
Project Status |
Completed (Fiscal Year 2020)
|
Budget Amount *help |
¥18,200,000 (Direct Cost: ¥14,000,000、Indirect Cost: ¥4,200,000)
Fiscal Year 2020: ¥2,080,000 (Direct Cost: ¥1,600,000、Indirect Cost: ¥480,000)
Fiscal Year 2019: ¥1,690,000 (Direct Cost: ¥1,300,000、Indirect Cost: ¥390,000)
Fiscal Year 2018: ¥14,430,000 (Direct Cost: ¥11,100,000、Indirect Cost: ¥3,330,000)
|
Keywords | 吸出しメカニズム / 空石積み / 九州北部豪雨 / 災害復興 / 集落会議 / 二極化した材料 / 気候変動 / 洪水 / 空石積み護岸 / 吸出し現象 / 水害 / 水理実験 / 吸出し / 護岸 / 破壊 / 水理メカニズム / 復旧工法 / 合意形成 / Eco-DRR / 強度 / 実験 / 北部九州豪雨 / 川幅拡大 / 砂河川 |
Outline of Final Research Achievements |
In this study, regarding the mechanism of erosion sedimentation expansion of the valley bottom plain that occurred in the granite area during the heavy rain in northern Kyushu that occurred in 2017, the promotion of riverbank erosion and the suppression of riverbed decline became remarkable in the polarized grain size. It is thought that gravel stays on the riverbed, which promotes riverbank erosion and suppresses riverbed decline. One of the reasons why the riverbed decline is suppressed is that the fine sand was shielded by armoring and was not drafted. In addition, a hydraulic experiment was conducted focusing on the phenomenon of fine sand coming out of the revetment. As a result, it was clarified that the suction phenomenon is caused by the unevenness of the revetment and is caused by the difference in water pressure inside. In addition, a village meeting was held with local residents regarding reconstruction, and a reconstruction plan was formulated.
|
Academic Significance and Societal Importance of the Research Achievements |
本研究では、細砂が存在する河川の浸食堆積メカニズムから発展し、空石積み工法の細砂の吸出しメカニズムに着目し、一定の成果を得た。近年、治水方式が流域治水へと転換している中で、流出抑制技術として護岸背後の空間や河岸域からの浸透機能の強化手法を考えているが、その際には空石積み工法からの吸出し現象や破壊形態に関する知見が必要である。また、災害が頻発する中で、災害復興時に地域との協働での復興計画立案手法の確立は大きな課題であるが、朝倉を対象に17集落46回の集落会議を開催し、その結果を分析し手法論についての成果が得られた。その結果は書籍としてまとめたが、球磨川の水害ですでに活用されている。
|