Field Verification of Superpave Dynamic Modulus

In the mechanistic-empirical pavement design guide, prediction of flexible pavement response and performance needs an input of dynamic modulus of hot-mix asphalt at all three levels of hierarchical inputs. This study was intended to find the best way to predict/derive this input. Nine Superpave pavement sections were selected as test sections in this study. Deflection data on all test sections was collected with a Dynatest 8000 falling weight deflectometer shortly after construction. The deflection data, normalized with respect to 40-kN load, were used to back-calculate asphalt layer moduli using three back-calculation algorithms. Laboratory dynamic modulus tests were conducted on asphalt concrete (AC) cores and laboratory-compacted samples. Dynamic modulus was also estimated with the Witczak model, new Witczak model, and Hirsch model. The results show that the AC moduli obtained from various back-calculation programs used in the study are generally comparable. Laboratory dynamic modulus is comparable at 4°C, but the variation increases as the test temperature increases. The Witczak model underestimates the dynamic modulus at low temperature and overestimates it at higher temperature. The parameter estimate when the laboratory dynamic modulus is used as a dependent variable and the moduli from other approaches as independent variables is close to 1. This is especially true for the AC moduli estimated by various prediction methods. The Hirsch model appears to be the best for estimation and is closely followed by the new Witczak model.

• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/08991561
• Authors:
  • Gedafa, Daba S
  • Hossain, Mustaque
  • Romanoschi, Stefan
  • Gisi, Andrew J
• Publication Date: 2010-5

Language

• English

Media Info

• Media Type: Print
• Features: Figures; References; Tables;
• Pagination: pp 485-494
• Serial:
  • Journal of Materials in Civil Engineering
  • Volume: 22
  • Issue Number: 5
  • Publisher: American Society of Civil Engineers
  • ISSN: 0899-1561
  • EISSN: 1943-5533
  • Serial URL: http://ascelibrary.org/journal/jmcee7

Subject/Index Terms

• TRT Terms: Asphalt mixtures; Deflection; Dynamic modulus of elasticity; Flexible pavements; Hot mix asphalt; Materials at high or low temperatures; Materials tests; Mathematical methods; Mathematical models; Mathematical prediction; Pavement design; Superpave
• Uncontrolled Terms: Pavement test sections
• Subject Areas: Highways; Materials; Pavements; I22: Design of Pavements, Railways and Guideways; I31: Bituminous Binders and Materials;

Filing Info

• Accession Number: 01159247
• Record Type: Publication
• Files: TRIS
• Created Date: Jun 16 2010 8:41AM