TEMPERATURE CORRECTION OF DEFLECTIONS AND BACKCALCULATED ASPHALT CONCRETE MODULI

A temperature correction procedure for deflections and backcalculated asphalt concrete (AC) moduli for flexible pavements in North Carolina is presented. The data used in developing this procedure were collected from four pavements in the Piedmont area of North Carolina with various types of layer materials and thicknesses. Four trips, one in each season, were made to each of these pavements so that deflections in the maximum range of temperatures could be obtained without significant structural deterioration of the pavements. During each trip deflection testing was conducted on an hourly basis for 1 full day per test section. Pavement surface and depth temperatures were measured at the time of deflection testing with a falling weight deflectometer. The measured deflection and temperature values were used to validate the temperature correction procedure presented in the 1993 AASHTO "Guide for Design of Pavement Structures". It was found that the AASHTO procedure produced significant errors in the corrected deflections. The main reasons for these errors were that the AASHTO mean temperature cannot account for the difference in temperature-depth gradients during heating versus cooling cycles and that the AASHTO temperature correction factors overcorrect the deflections at higher temperatures. A new temperature correction procedure for deflections and backcalculated moduli was developed on the basis of the fact that the middepth temperature of the AC layer is an effective AC layer temperature. The accuracy of this procedure was validated with deflection and surface temperature data collected from four other pavement sections in North Carolina.

Language

  • English

Media Info

  • Features: Figures; References; Tables;
  • Pagination: p. 55-62
  • Monograph Title: Strength and deformation characteristics of pavement sections and pavement rehabilitation
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00682839
  • Record Type: Publication
  • ISBN: 0309061121
  • Files: TRIS, TRB, ATRI
  • Created Date: Aug 24 1995 12:00AM