ESTIMATION OF FROST HEAVE RATIO OF SOILS IN CONTEMPLATION OF MATRIC SUCTION UNDER LOW OVERBURDEN PRESSURE

低土被り圧下の不飽和路床土の凍上量の推定方法の提案

This study proposes two kinds of estimation methods for the frost heave ratio of unsaturated frost-susceptible soils under low overburden pressure such as subgrade soils at the pavement structure in cold regions. One is the modified Takashi's equation in contemplation of matric suction of soils under low overburden pressure. The other is the simple frost heave model which evaluates the effects of initial water content, Bishop's effective stress and water absorption during freezing on the frost heave ratio. In addition, the applicability and the usefulness of both methods were discussed based on the results of frost susceptibility tests. As the results, it was revealed that the estimation methods proposed in this study have an excellent applicability to the precise prediction for the frost-heave phenomenon of unsaturated subsurface ground in cold regions.　土の凍上量の予測式として「高志の式」が多用されているが，同式は土被り圧100kPa以上の飽和地盤で有効と考えられており，表層地盤などの不飽和状態の低土被り圧領域では，予測値が実際よりも大きくなる傾向にある．本研究では，寒冷地舗装構造の路床を想定した低土被り圧下における不飽和土の凍上量の推定方法として，有効応力を土被り圧とサクションの和で表した修正高志の式と吸水量，有効土被り圧，初期飽和度等を考慮可能な簡易凍上モデルを提案した．また，表層地盤を模擬した低い上載圧の凍上試験と保水性試験を行い，従来式と提案式を用いて試験結果をフィッティングしそれぞれの適用性を検証した．その結果，低土被り圧領域では，修正高志の式や簡易凍上モデルの予測精度が従来式よりも向上することを明らかにした．

• Record URL:
  • https://doi.org/10.2208/jscejpe.70.I_65
• Summary URL:
  • http://scholar.google.com/scholar_lookup?title=ESTIMATION+OF+FROST+HEAVE+RATIO+OF+SOILS+IN+CONTEMPLATION+OF+MATRIC+SUCTION+UNDER+LOW+OVERBURDEN+PRESSURE&author=T.+Ishikawa&author=I.+KIJIYA&author=T.+Tokoro&author=S.+Akagawa&publication_year=2015
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/21856559
• Authors:
  • Ishikawa, Tatsuya
  • KIJIYA, Ippei
  • Tokoro, Tetsuya
  • Akagawa, Satoshi
• Publication Date: 2015

Language

• English
• Japanese

Media Info

• Media Type: Web
• Pagination: pp I_65-I_70
• Serial:
  • Journal of Japan Society of Civil Engineers, Ser. E1 (Pavement Engineering)
  • Volume: 70
  • Issue Number: 3
  • Publisher: Japan Society of Civil Engineers
  • ISSN: 2185-6559
  • Serial URL: https://www.jstage.jst.go.jp/browse/jscejpe/-char/en

Subject/Index Terms

• TRT Terms: Frigid regions; Frost heaving soils; Moisture content; Overburdens; Pavements; Subgrade (Pavements); Unsaturated soils
• Subject Areas: Geotechnology; Highways; Pavements; I52: Construction of Pavements and Surfacings;

Filing Info

• Accession Number: 01564499
• Record Type: Publication
• Source Agency: Japan Science and Technology Agency (JST)
• Files: TRIS, JSTAGE
• Created Date: May 26 2015 4:12PM