The purpose of this investigation was to evaluate the in-situ performance of Mirafi 140 fabric in the construction of soil-aggregate and granular surface roadways overlying frost-susceptible fined grained subgrades. The following general conclusions were derived from the investigation: there is a reinforcement capability when Mirafi 140 is interlayered between a soil aggregate surface and a frost-susceptible subgrade; laboratory freeze-thaw tests of a frost-susceptible fine grained soil interlayered with one or more Mirafi 140 fabric discs indicated a reasonable control of freeze-thaw elongation and some degree of improvement of parameters due to reinforcement both prior to and after subjection to freeze thaw; over the three years of this study, Iowa experienced the oldest winter since 1936; on the basis of in-situ Benkelman beam deflections and relative stiffners value, plus moduli of subgrade reactions and deformations determined from plate-bearing tests, Mirafi 140 fabric performed most favorably as a reinforcement between a soil-aggregate surface and frost-prone subgrade. Based on the in-situ Benkelman beam and plate bearing parameters, use of Mirafi 140 fabric in conjunction with granular backfill in an undercut frost-subgrade soil does not appear significantly justifiable. Based on the various performance parameters, use of Mirafi 140 fabric does not appear justifable as a reinforcement between a soil-aggregate surface, and stable non-frost-susceptible subgrade or between a macadam base and other frost or non-frost-susceptible subgrades; use of Mirafi 140 fabric as a reinforcement for frost-susceptible secondary roads should probably be limited to apparent and/or suspected areas of frost-prone subgrades underlying base and/or surface materials having less rigidity than a macadam base, and field soil moisture may be a highly relevant factor in soil-fabric bending characteristics and should be studied in much greater detail.

  • Corporate Authors:

    Engineering Research Institute

    Iowa State University, 104 Marston Hall
    Ames, IA  United States  50010
  • Authors:
    • Hoover, J M
    • Pitt, J M
    • Handfelt, L D
    • STANLEY, R L
  • Publication Date: 1980-5

Media Info

  • Features: Figures; References; Tables;
  • Pagination: 112 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00316487
  • Record Type: Publication
  • Report/Paper Numbers: ISU-ERI-AMES-80211 Final Rpt.
  • Files: TRIS
  • Created Date: Dec 30 1980 12:00AM