For many years the airfield pavement industry has been searching for a suitable nondestructive method that would eliminate the necessity for borings and test pits. This paper describes the use of the Waterways Experiment Station 7257-kg (16-kip) vibrator for the evaluation of load-carrying capacity and the design of bituminous concrete overlays for highly variable flexible pavements at commercial airports. The primary purpose of using dynamic testing was to provide a rapid, nondestructive, and independent system of measurement of existing pavement strength. The vibrator is electrohydraulic and can apply loads up to 66.7 kN (15 000 lbf) on a 45.7-cm-diameter (18-in-diameter) plate at frequencies of 5 to 100 Hz. Primary measurements included dynamic stiffness testing, borings with California bearing ratio tests, and condition surveys. Dyanmic stiffness was correlated with physical condition and types and thicknesses of pavement and subgrade to determine allowable gross loads and overlay thicknesses. The study shows that the stiffness concept in which a large vibratory load is used relates well to conventional (California bearing ratio) methods provided that sufficient conventional data are available at a limited number of locations representing the range of conditions. The immediate potential values of this method are speed of field operation, unexpected ranges of strength, and convenience of a single parameter expression of overall pavement and subgrade strength. Potential improvements in dynamic nondestructive methodolgy include use of deflection basin data and relation of stiffness to a theoretical basis. /Author/

Media Info

  • Media Type: Print
  • Pagination: pp 100-106
  • Monograph Title: Pavement design, evaluation and performance
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00156012
  • Record Type: Publication
  • ISBN: 0309220710
  • Files: TRIS, TRB
  • Created Date: Aug 15 1977 12:00AM