Study on the Mechanism of Consistensy limit of Clay

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K06485
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Geotechnical engineering
• Research Institution: Iwate University
• Principal Investigator: Okawara Masafumi 岩手大学, 理工学部, 准教授 (80223741)
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: コンシステンシー限界 / 分子動力学 / 加速器実験 / 水分子

Outline of Final Research Achievements

Type tests using small-angle X-ray scattering method were conducted to elucidate the mechanism of consistency in Na-montmorillonite. Based on the test results, in the solid state to semi-solid state, there was crystalline swelling in which the molecular water layer thickness increased stepwise, whereas in the plastic state to liquid state, there was osmotic swelling in which the distance between particles continually increased. An evaluation of the orientation of the clay particles from the X-ray scattering images revealed that, while the particles were randomly oriented in the solid state to semi-solid state, they became oriented ordered in the plastic state. Furthermore, in the liquid state, it was observed that the particle orientation became random again.

Free Research Field

地盤工学

Academic Significance and Societal Importance of the Research Achievements

土の基本物性として重要なコンシステンシー限界について，ミクロの観点から解釈を与えている。すなわち塑性限界が水分子を急激に吸水する点であり，液性限界は粘土が塑性体から液体に徐々に変化していくときの境界であり，実際は幅を持っていることが明らかになった。地盤工学上，重要な基本物性の理解に貢献している。