The Resistance Value (R-value) is commonly used by the Hawaii Department of Transportation engineers to design the thickness of flexible pavements. Direct measurements of the R-value require equipment that is not readily available to most practicing engineers in the state of Hawaii. Typically, the R-value is indirectly based on the results of California Bearing Ratio (CBR) tests. Knowing the CBR, the R-value is estimated based on published correlations. However, these correlations were established for soils outside the state of Hawaii. Moreover, these correlations were not established for directly relating R-value and CBR but rather, for estimating other parameters such as resilient modulus, soil support value or modulus of subgrade reaction. CBR, R-value and index tests were performed on tropical residual soils from four locations on the island of Oahu in the state of Hawaii. Based on the test results, five correlations were developed to estimate the R-value. Among these procedures is one relating the R-value to index properties alone without the CBR. The limitations of each procedure and the choice of method are discussed. Some tropical residual soils can undergo irreversible changes upon drying. One of the soils sampled had a relatively high natural water content. As a secondary objective, this soil was tested at three different stages of drying: first at its natural or in situ state, second after oven-drying the soil; and third after drying the soil to approximately half its natural water content. This material can be regarded as three different soils corresponding to the various stages of drying. Significant increases in the CBR and R-values were observed from the in situ to the oven-dry samples. The oven-dry samples were excluded from the correlations described above because these soils were dried to temperature extremes that regular soils do not experience, and therefore, are judged to be inappropriate for inclusion in the correlations.

  • Corporate Authors:

    University of Hawaii, Manoa

    Department of Civil and Environmental Engineering, 2540 Dole Street
    Honolulu, HI  United States  96822

    Hawaii Department of Transportation

    869 Punchbowl Street
    Honolulu, HI  United States  96813-5097

    Federal Highway Administration

    1200 New Jersey Avenue, SE
    Washington, DC  United States  20590
  • Authors:
    • Ooi, PSK
    • Hashiro, R S
  • Publication Date: 2005-1-25


  • English

Media Info

  • Features: Appendices; Figures; Photos; References; Tables;
  • Pagination: 109 p.

Subject/Index Terms

Filing Info

  • Accession Number: 00989230
  • Record Type: Publication
  • Report/Paper Numbers: HWY-L-2000-03,, Final Report
  • Contract Numbers: 46511
  • Created Date: Apr 15 2005 12:00AM