DETERMINATION OF LAYER MODULI FROM FWD MEASUREMENTS

In this study, a comparison of two backcalculation programs with different calculation methods, Modulus and Elmod, is made using Falling Weight Deflectometer (FWD) data derived from 43 SHRP-LTPP (Strategic Highway Research Program, Long-Term Pavement Performance) test sections in Finland. Higher subgrade modulus values are obtained with the Elmod-program than with the Modulus-program. Consequently, the Modulus-program yields higher values for asphalt layer modulus than the Elmod-program. Variation in the backcalculated layer moduli is somewhat greater within the Modulus-program than the Elmod-program. The base course modulus was found to be the most stress-sensitive of pavement layers, since the stress level is also highest in the base course of unbound pavement layers. Critical strains were calculated using the linear program (BISAR) with layer moduli from the Modulus-program as input and with the Elmod-program. It was found, that the calculated strains from the two programs agree very well, even though the calculated moduli are quite different. (A) For the covering abstract see IRRD 883133.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/isbn/9054105232
• Corporate Authors:

  AA Balkema

  P.O. Box 1675
  Rotterdam,   Netherlands  BR-3000
• Authors:
  • RUOTOISTENMAKI, A
• Publication Date: 1996

Language

• English

Media Info

• Features: References;
• Pagination: p. 347-54
• Serial:
  • FLEXIBLE PAVEMENTS. PROCEEDINGS OF THE EUROPEAN SYMPOSIUM EUROFLEX 1993 HELD IN LISBON, PORTUGAL, 20-22 SEPTEMBER 1993
  • Publisher: AA Balkema

Subject/Index Terms

• TRT Terms: Base course (Pavements); Coefficients; Conferences; Deflectographs; Deformation; Flexible pavements; Stresses; Subgrade (Pavements); Wearing course (Pavements)
• ITRD Terms: 2990: Basecourse; 6410: Coefficient; 8525: Conference; 6187: Deflectograph; 5595: Deformation; 2944: Flexible pavement; 2961: Roadbase; 5575: Stress (in material); 2950: Subgrade; 2980: Wearing course
• Subject Areas: Data and Information Technology; Highways;

Filing Info

• Accession Number: 00729628
• Record Type: Publication
• Source Agency: Transport Research Laboratory
• ISBN: 90-5410-523-2
• Files: ITRD
• Created Date: Dec 26 1996 12:00AM