PREDICTING FIELD COMPACTED STRENGTH AND VARIABILITY

A sheepsfoot and a rubber-tired roller compacted samples in the field that were tested to determine how water content, dry density, and compactive effort affect the magnitude and variability of the unconfined shear strength of a glacial, silty clay soil. The samples taken were tested in both the as-compacted and the soaked conditions. Statistical analyses were used to determine the most useful predictive models for the dry density and shear strength for each roller type and soil condition. In all cases, only the wet-or-optimum water content results could be studied. The regression models for the as-compacted unconfined strength indicated that water content and compactive effort were the most influential variables regardless of the roller type and had the greatest effect on the soaked strength of the soil compacted by the rubber-tired roller. No significant model was found for the soaked soil compacted by the sheepsfoot roller. Variability from field operations appears to be a major cause of differences between field and laboratory compacted soils. Variability in the magnitude of unconfined strength in the field was found to be significant, predictable, and larger than in the laboratory and prevents consistently accurate determination of the true state of the compacted mass by a few samples. This variability can be reduced by controlling variability of the water content at compaction. /Authors/

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 42-48
  • Monograph Title: Subdrainage and soil moisture
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00301588
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: Dec 19 1979 12:00AM