STABILIZATION OF EXPANSIVE SHALE CLAY BY MOISTURE-DENSITY CONTROL

Stabilization of expansive Pierre shale has been a continuing problem in South Dakota for many years. A procedure has been developed to produce a roadbed with very few differentials that uses special undercutting to a depth of 1.83m (6 ft), replacement of subgrade by selected materials, rigid control of moisture to achieve low density at a high moisture content, and lime treatment in the upper 15.2 cm (6 in) of subgrade. A density of 92 percent of the maximum American Association of State Highway and Transportation Officials T 99 test value and a moisture content of 3 percent above the optimum were set as targets. The high degree of stability of roads constructed by this procedure is shown by the very good roughness-index ratings. The average roughness index, based on a 0 to 5 rating system, is 4.34 for the full length of 209.2 km (130 miles) of surfacing. The projects observed and tested for this study have been inservice from 5 to 8 years.

Media Info

  • Media Type: Print
  • Features: Figures; Maps; References; Tables;
  • Pagination: pp 11-17
  • Monograph Title: Stabilization of soils
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00177112
  • Record Type: Publication
  • ISBN: 0309026709
  • Files: TRIS, TRB
  • Created Date: Jun 28 1978 12:00AM