One of the critical field problems of compacted clay soils used as subgrades for pavement structures is related to the deformation and swelling that result from water absorption. this paper describes the swelling characteristics of five composite B-horizon soils belonging to the Renfrow series that are encountered throughout north-central Oklahoma. Unlike the C-horizon soils in this area, the soils reported on here are sufficiently weathered and not well cemented. This was verified by the fact that neither the clay-size portion nor the plasticity index of these soils increased substantially after ultrasonic degradation. Laboratory specimens compacted to maximum dry density at optimum moisture content were tested by using the constant-volume and free-swell methods. The volume increased with the logarithm of the time; the initial phases showed higher rates of moisture uptake than did the final stages. This and the other relationships among swelling pressures, volume changes, moisture uptake, and physicochemical properties were generally characterized by a band pattern that implied the existence of upper and lower limits of swelling response. In addition, the reaction potential, which serves as a good predictor of volume changes and swelling pressures for C-horizon soils, did not have the accuracy expected. Scanning electron microscopy data indicated that swelling pressure and volume increase in direct proportion to the void cross-sectional area. (Authors)

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 91-94
  • Monograph Title: Mechanics of track support, piles and geotechnical data
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00315305
  • Record Type: Publication
  • ISBN: 0309029880
  • Files: TRIS, TRB
  • Created Date: Sep 16 1980 12:00AM