2022 Fiscal Year Final Research Report
Evaluation of freezing damage of soil pavement using X-ray CT image analysis and pore size measurement
Project/Area Number |
18K04300
|
Research Category |
Grant-in-Aid for Scientific Research (C)
|
Allocation Type | Multi-year Fund |
Section | 一般 |
Review Section |
Basic Section 22010:Civil engineering material, execution and construction management-related
|
Research Institution | Shinshu University |
Principal Investigator |
|
Co-Investigator(Kenkyū-buntansha) |
梅崎 健夫 信州大学, 学術研究院工学系, 教授 (50193933)
|
Project Period (FY) |
2018-04-01 – 2023-03-31
|
Keywords | 歩行者系舗装 / 土系舗装 / X線CTスキャナ / 細粒分含有率 / 細孔径分布 / 凍結融解 / 弾性波速度 / 圧縮強度 |
Outline of Final Research Achievements |
In order to investigate the freezing damage process and mechanism of soil pavement, repeated freezing and thawing tests combined with X-ray CT image analysis, porosimeter, elastic wave velocity and uniaxial compression test were performed on soil pavement specimens with different fine particle contents. As the result, due to the precision limit of our X-ray CT scanner, it was not possible to quantitatively evaluate the freezing damage process. However, we visually confirmed that cracks progressed gradually from the surface to the inside during freezing. And, it was shown that when the fine particle content is high, the effect of freezing damage is large, and there are many micro voids. In this study, no correlation was observed between freezing damage and strength of the specimen. It is suggested that the freezing damage of soil pavement depends on the permeability rather than the strength of the material.
|
Free Research Field |
地盤工学
|
Academic Significance and Societal Importance of the Research Achievements |
表面(凍結面)から内部への凍結速度,凍害劣化進行の定量評価には至らなかったものの,主材料の土質材料の特性と同様に,細粒分含有率が高いほど凍害劣化の影響を受けやすいことを明らかにした.一方,粒度試験(細粒分含有率)と弾性波速度試験の結果によって,圧縮強度を予測することが可能であることを示した.実施工においては,施工時の主材料の細粒分含有率を把握しておくことにより,定期的に弾性波速度によって圧縮強度を予測し,舗装の健全度を評価することが可能であると考えられる.土系舗装に凍害劣化には,材料の強度よりも透水性に依存することが示唆されることから,今後,凍害劣化と透水性との関係性に関する検討も望まれる.
|