This synthesis report will be of interest to pavement and geotechnical design and research engineers, geologists and engineering geologists, and similar laboratory personnel. It describes the current practice for measuring the in situ mechanical properties of pavement subgrade soils. The tests conducted to estimate the mechanical properties of soil strength and stiffness are the primary topics, and these are discussed in the context of design procedures, factors affecting mechanical properties, and the variability of measurements. Information for the synthesis was collected by surveying U.S., Canadian, and selected European transportation agencies and by conducting a literature search. This report of the Transportation Research Board provides information on existing and emerging technologies for static and dynamic, and destructive and nondestructive testing for measuring in situ mechanical properties of pavement subgrade soils. Correlations between in situ and laboratory tests are presented. The effects of existing layers on the measurement of subgrade properties, and the subjects of soil spatial and seasonal variability are also discussed. Most importantly, the use of measured soil properties in pavement design and evaluation are explained. New applications or improvements to existing in situ test methods to support the use of mechanistic/stochastic-based pavement design procedures are also explained.

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    • Distribution, posting, or copying of this PDF is strictly prohibited without written permission of the Transportation Research Board of the National Academy of Sciences. Unless otherwise indicated, all materials in this PDF are copyrighted by the National Academy of Sciences. Copyright © National Academy of Sciences. All rights reserved
  • Corporate Authors:

    Transportation Research Board

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  • Authors:
    • Newcomb, D E
    • Birgisson, B
  • Publication Date: 1999


  • English

Media Info

  • Features: Appendices; Figures; References; Tables;
  • Pagination: 79 p.
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00780294
  • Record Type: Publication
  • ISBN: 0309068576
  • Report/Paper Numbers: Project 20-5 FY 1996, Topic 29-08
  • Files: TRIS, TRB, ATRI
  • Created Date: Dec 21 1999 12:00AM