Root-soil-water coupling simulator for numerical simulation of agricultural facility.

2021 Fiscal Year Final Research Report

• Project/Area Number: 20K22599
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0604:Agricultural economics and rural sociology, agricultural engineering, and related fields
• Research Institution: Tokyo Institute of Technology (2021); National Institute of Technology, Toyota College (2020)
• Principal Investigator: Tomobe Haruka 東京工業大学, 環境・社会理工学院, 助教 (90880005)
• Project Period (FY): 2020-09-11 – 2022-03-31
• Keywords: 有限要素法 / 接触力学 / 不飽和土 / 成長 / 植物力学

Outline of Final Research Achievements

Plant roots hold soil particles in a web-like structure on natural and man-made slopes, thus contributing to slope stabilization. On the other hand, plant roots can also break up hard tillage beds and soften the soil in wastelands and agricultural lands. Both of these effects are positive/negative reinforcing effects of plant roots on the soil. To estimate and utilize the reinforcing effects, it is necessary to mechanically predict and evaluate the process of plant root growth and soil penetration. Through this study, we have developed a mathematical basis for 2-D and 3-D numerical simulations of the growth process of plant roots of arbitrary shapes under various soil moisture conditions, initial stress distributions, and boundary conditions.

Free Research Field

農業農村工学

Academic Significance and Societal Importance of the Research Achievements

研究成果は，土質力学と植物科学を架橋する領域横断的研究であり，土質力学分野で用いられてきた有限要素法によるシミュレーション手法に，植物科学分野で蓄積のある微視的な組織構造や伸長メカニズムを加えた新たな数理モデル基盤を創出した．また，研究成果の具体例として，実際に実生ダイコン個体の伸長過程シミュレーションを行い，実験結果と比較することで，伸長領域側面の応力状態により植物根の伸長しやすさが異なることや，植物根は，土に三叉状の応力集中箇所を生じさせることで貫入しやすい応力構造を生み出すことが示唆された．今後，エネルギー効率の良い地盤基礎構造物施工技術の開発や，作物栽培・育種への応用が期待される．