Implementation of mechanistic pavement design : field and laboratory implementation.

Details

• Creators:
  Maher, Ali ; Gucunski, Nenad ; Bennert, Thomas
• Corporate Creators:
  Rutgers University. Center for Advanced Infrastructure and Transportation
• Corporate Contributors:
  United States. Department of Transportation. Research and Innovative Technology Administration ; United States. Federal Highway Administration
• Subject/TRT Terms:
  • Asphalt pavements
  • Pavement design
  • Road construction
  • Implementation
  • Laboratory tests
  • Field tests
  • Mechanistic design
  • Pavements, Asphalt--Design and construction
  • Pavements--Design and construction
• Publication/ Report Number:
  ELF-RU7072
• Resource Type:
  Tech Report
• Geographical Coverage:
  New Jersey
• Edition:
  Final report; Jan. 2002-Dec. 2005.
• Corporate Publisher:
  Rutgers University. Center for Advanced Infrastructure and Transportation
• Abstract:
  One of the most important parameters needed for 2002 Mechanistic Pavement Design Guide is the dynamic modulus (E*). ; The dynamic modulus (E*) describes the relationship between stress and strain for a linear viscoelastic material. The E* is the ; prime material parameter used for calculating both rutting and fatigue cracking in hot mix asphalt. The parameter is ; traditionally measured in the laboratory under an axial compressive type testing condition. Under the recommendations of the ; 2002 Mechanistic Design Guide, this is the preferred method for reconstruction or new construction. However, if a ; rehabilitation is to be conducted, the 2002 Mechanistic Design Guide prefers the use of the Falling Weight Deflectometer ; (FWD) because of its capability of determining the E* parameter in-situ and in a non-destructive way. Unfortunately, this is not ; 100% true since most PMS procedures require that cores of the pavement be taken so accurate layer thickness’ can be ; determined for back-calculation purposes. If FWD testing is not available, then the 2002 Mechanistic Design Guide ; recommends using the laboratory testing of cores from the pavement. ; Research showed that shear modulus testing (G*) from the Superpave Shear Tester provides modulus values from readily ; attained cores. The 50 mm samples required by the SST can easily be cut from 6 inch diameter cores. However, as indicated, ; the G* values obtained can not be directly used in the 2002 Mechanistic Pavement Design Guide without using an assumed ; Poisson’s Ratio and elastic theory concepts that relate G* to E* (Dynamic Modulus). Intact cores can be taken and trimmed to ; provide dynamic modulus test specimens, as long as the asphalt pavement thickness is greater than 6 inches thick. A Master ; Stiffness Curve can then be developed using the E* data determined at various test temperatures and loading frequencies and ; shifted to the in-situ asphalt pavement temperature. In all test sections evaluated in the study, the Falling Weight ; Deflectometer (FWD) back-calculated asphalt modulus showed excellent correlation the corresponding Master Stiffness Curve, ; when it was assumed that the loading frequency of the FWD is 16.7 hertz. This illustrates that if field testing is not available, ; cores can be taken and tested using the dynamic modulus testing protocol to provide reasonable estimates of the asphalt ; modulus. And, although further validation is required, the generated Master Stiffness Curve should provide a reasonable ; estimate of the seasonal variation in asphalt modulus, which would required the FWD to test the identical location at least once ; every month of a full year.
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• Format:
  PDF
• Download URL:
  https://rosap.ntl.bts.gov/view/dot/18367/dot_18367_DS1.pdf
• File Type:
  [PDF - 569.13 KB]
• Collection(s):
  US Transportation Collection
• Main Document Checksum:
  urn:sha256:f79a78a5579730cb6cdf8114b25691de6a30dbba50cef37b0853b9e2a7c201cc