PAVEMENT-LAYER MODULAR RATIOS FROM DYNAFLECT DEFLECTIONS

Pavement systems and individual layers were evaluated by using the deflections obtained with the Dynaflect device. The pavements were considered to be three-layer systems, and the deflection data were used to estimate ratios of the elastic moduli of the adjacent layers (K1 and K2). These ratios reduce the systems from these values of elastic modulus to two values of modular ratio. Certain assumptions were made related to pavement factors that affect deflections and also the elastic modulus of the asphalt concrete layer (E1). A graphical trial-and-error procedure was used to match the surface deflections calculated by using the Chevron program for the Dynaflect load with the actual deflections measured on the roadway. The results obtained were related to (a) time-of-year effects, (b) range of values of K1 and K2, (c) effects of the assumed value of E1 on the estimated values of the moduli of the base and subbase (E2 and E3 respectively), (d) effects of elevation on E1/E2 (i.e., K1), and (e) suggested modification of the locations of the Dynaflect geophones.

Media Info

  • Media Type: Print
  • Features: Figures; References; Tables;
  • Pagination: pp 23-28
  • Monograph Title: Analysis of pavement systems
  • Serial:

Subject/Index Terms

Filing Info

  • Accession Number: 00193377
  • Record Type: Publication
  • Files: TRIS, TRB
  • Created Date: May 11 1979 12:00AM