COMPUTATION OF SUBGRADE STRENGTH AT FIELD CONDITIONS

This paper presents the results of some field and laboratory investigations of test sections of pavement in India, and describes some correlations derived for computing subgrade strength in field conditions. The test sections were studied for determining the thicknesses of different layers. Use was made of the Modified Structural Number (MSN), which is an important parameter for pavement deterioration models, and requires evaluation of subgrade strength under field conditions. It is the Structural Number (SN) plus a specific function of CBR. The SN expresses pavement strength in terms of the thickness and strength of the pavement's layers, and the CBR is the subgrade strength under unsoaked field conditions. The field observations included measurements of the thickness of pavement layers, and of the subgrade's dry density and moisture content. The subgrade soil samples were subjected to various laboratory tests, and the data were subjected to multiple regression analysis. It was found that unsoaked CBR can be estimated reasonably accurately from the field and laboratory data, in terms of five specific parameters. This considerably reduces the inputs needed for conducting CBR tests.

  • Availability:
  • Corporate Authors:

    Indian Roads Congress

    Jamnagar House, Shahjahan Road
    New Delhi,   India  110 011
  • Authors:
    • SOOD, V K
    • Joshi, P
  • Publication Date: 1995-7

Language

  • English

Media Info

  • Pagination: p. 9-14
  • Serial:
    • Indian Highways
    • Volume: 23
    • Issue Number: 7
    • Publisher: Indian Roads Congress
    • ISSN: 0376-7256

Subject/Index Terms

Filing Info

  • Accession Number: 00715948
  • Record Type: Publication
  • Source Agency: Transport Research Laboratory
  • Files: ITRD
  • Created Date: Jan 31 1996 12:00AM