PERFORMANCE OF SOIL-AGGREGATE-FABRIC SYSTEMS IN FROST-SUSCEPTIBLE ROADS, LINN COUNTY, IOWA
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.
Engineering Research InstituteIowa State University, 104 Marston Hall
Ames, IA USA 50010
- Hoover, J M
- Pitt, J M
- Handfelt, L D
- STANLEY, R L
- Publication Date: 1980-5
- Features: Figures; References; Tables;
- Pagination: 112 p.
- TRT Terms: Backfilling; Benkelman beam; Fabrics; Field tests; Fine grained soils; Freeze thaw tests; Freezing; Frost susceptible soil; Performance; Plate bearing test; Secondary roads; Soil aggregates; Subgrade (Pavements); Thaw
- Uncontrolled Terms: Freeze thaw cycles
- Old TRIS Terms: Backfills; Insitu methods
- Subject Areas: Geotechnology; Highways; Materials; I33: Other Materials used in Pavement Layers;
- Accession Number: 00316487
- Record Type: Publication
- Report/Paper Numbers: ISU-ERI-AMES-80211 Final Rpt.
- Files: TRIS
- Created Date: Dec 30 1980 12:00AM