THERMAL EROSION OF CUT SLOPES IN ICE-RICH SOIL

Experience with cuts in ice-rich soil has shown that significant slope deformation and down-slope movement of soil can result as the frozen material along the slope face thaws. This report presents data from a test site constructed by Alyeska Pipeline Service Company in 1973 to evaluate the effect of various types of surface treatments on the performance of ice-rich cut slopes. The test site, located near Hess Creek, Alaska (approximately 5 miles north of Fairbanks), consisted of five test sections with the following surface treatments: 1) urea formaldehyde foam (4") over excelsior mulch, 2) two layers of excelsior mulch, 3) two layers of excelsior mulch over burlap or Dynel nylon fabric, 4) urea formaldehyde foam (2") or Dynel nylon fabric over sand, 5) untreated (bare soil). The test sections were monitored during the 1973 and 1974 summer seasons. Longer term performance of the test sections was evaluated during two field investigations conducted during the 1983 summer season. Results from these two investigations and from 1973 and 1974 observations indicate that surface treatments with higher insulative properties (i.e., foam insulation) can reduce thermal erosion in ice-rich soil forr a limited number of thaw seasons. Other surface treatments were relatively ineffective in reducing thermal erosion even during the first thaw season. Longer term stability in terms of soil displacement appears to be related to initial ice content of the frozen soil and shear strength of the thawing soil. All slopes at the Hess Creek test site appeared to have been stable in 1983. Vegetation was well established in most of the test sections. (Author)

• Record URL:
  http://www.dot.state.ak.us/stwddes/research/assets/pdf/fhwa_ak_rd_85_02.pdf
• 
• Corporate Authors:

  R&M Consultants, Incorporated

  P.O. Box 2630
  Fairbanks, AK  United States  99707

  Alaska Department of Transportation and Public Facilities

  Pouch Z
  Juneau, AK  United States  99811

  Federal Highway Administration

  1200 New Jersey Avenue, SE
  Washington, DC  United States  20590
• Authors:
  • Mageau, D W
  • Rooney, J W
• Publication Date: 1984-4

Media Info

• Features: Appendices; Figures; References; Tables;
• Pagination: 94 p.

Subject/Index Terms

• TRT Terms: Burlap; Embankments; Erosion; Formaldehyde; Geotextiles; Mulches; Nylon; Permafrost; Prevention; Slope stability; Surface treating; Thaw; Urea
• Subject Areas: Geotechnology; Highways; Security and Emergencies; I42: Soil Mechanics;

Filing Info

• Accession Number: 00391660
• Record Type: Publication
• Report/Paper Numbers: FHWA-AK-RD-85-02 Final Rpt.
• Contract Numbers: F46702
• Files: TRIS, USDOT, STATEDOT
• Created Date: Jan 30 1985 12:00AM