Development of numerical model of mixed soil considering the cohesive force of clay

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K18156
• Research Category: Grant-in-Aid for Young Scientists (B)
• Allocation Type: Multi-year Fund
• Research Field: Hydraulic engineering
• Research Institution: Nagoya University
• Principal Investigator: CHO Yonghwan 名古屋大学, 工学研究科, 助教 (00761082)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 混合土砂 / 粘着力 / 粘土流失 / 粘土含有率 / 漂砂

Outline of Final Research Achievements

This study presents the method to calculate sediment transport of mixed soil consisting of sand and clay based on the influence of clay loss from mixed soil bed on the initial motion of mixed soil. Two-dimensional laboratory experiments were conducted to investigate the characteristics of clay loss from mixed soil with the different wave conditions and the clay contents, and the characteristics of the spatial distribution of clay after the change of topography. In addition, based on the experimental results, the sediment transport model of mixed soil in the consideration of the clay loss phenomenon attributing to the change of the clay content was proposed and the validation and the sensitivity analysis of the model were examined.

Free Research Field

海岸工学，漂砂

Academic Significance and Societal Importance of the Research Achievements

混合土砂の地形変化は，粘土が一定量流失した後に生じること，混合土砂の粘土支配的，あるいは砂支配的な挙動はある粘土含有率で分類されることが判明した．さらに，地形形成過程において粘土の粘着力は，地形変動を遅延させる効果があるものの，粘土の含有率が小さい場合，時間の経過に伴った粘土の流失によって砂と同様な地形変化の傾向があることが明らかとなった．なお，これらの結果を踏まえて構築した混合土砂の計算モデルによって，混合土砂の移動特性についての理解がより深まると期待される．