Recalibration of the Asphalt Layer Coefficient
Publication: Journal of Transportation Engineering
Volume 137, Issue 1
Abstract
While there is an increasing interest in mechanistic-empirical flexible pavement design, this methodology will likely not be implemented by the majority of transportation agencies for several more years. Therefore, there is a need for optimization of the current design methodology, which for many agencies, is the 1993 AASHTO design guide. This approach contains a flexible pavement design equation with inputs of soil modulus, traffic, structural number, reliability, variability, and change in serviceability. A sensitivity analysis conducted on the inputs to this equation showed that the HMA layer coefficient is the most influential on the resulting HMA thickness. A recalibration of was performed using data from the National Center for Asphalt Technology Test Track. A least-squares regression was performed to minimize the error between predicted and actual equivalent single axle loadings applied to the test sections. The resulting average was 0.54 with a standard deviation of 0.08. Using 0.54 instead of the AASHTO recommended coefficient (0.44) results in a HMA thickness savings of approximately 18%.
Get full access to this article
View all available purchase options and get full access to this article.
References
AASHTO. (1993). AASHTO guide for design of pavement structures, Washington, D.C.
Al-Omari, B., and Darter, M. I. (1994). “Relationships between international roughness index and present serviceability rating.” Transp. Res. Rec., 1435, 130–136.
Corree, B. J., and White, T. D. (1989). “The synthesis of mixture strength parameters applied to the determination of AASHTO layer coefficient distributions.” Asph. Paving Technol., 58, 109–141.
Davis, K. P. (2009). “Recalibration of the asphalt layer coefficient.” MS thesis, Auburn Univ., Auburn, Ala.
Davis, K. P., and Timm, D. H. (2009). “Recalibration of the asphalt layer coefficient.” Rep. No. 09-03, National Center for Asphalt Technology (NCAT), Auburn, Ala.
Holman, F. (2003). IRI correlation exercise, Dept. of Transportation, Montgomery, Ala.
Hossain, M., Habib, A., and LaTorella, T. M. (1997). “Structural layer coefficients of crumb-rubber modified asphalt concrete mixtures.” Transp. Res. Rec., 1583, 62–70.
HRB. (1962). “The AASHO road test.” Special Rep. 61A, 61C, 61E, National Research Council, Washington, D.C.
Jess, J. C., and Timm, D. H. (2005). “Structural coefficients for new asphalt mixtures.” ALDOT Project No. 930-559, National Center for Asphalt Technology, Auburn Univ., Auburn, Ala.
Pologruto, M. (2001). “Procedure for use of falling weight deflectometer to determine AASHTO layer coefficients.” Transp. Res. Rec., 1764, 11–19.
Romanoschi, S., and Metcalf, J. B. (1999). “Simple approach to estimation of pavement structural capacity.” Transp. Res. Rec., 1652, 198–205.
Taylor, A. J., and Timm, D. H. (2009). “Mechanistic characterization of resilient moduli for unbound pavement layer materials.” Rep. No. 09-06, National Center for Asphalt Technology (NCAT), Auburn, Ala.
Timm, D. H. (2009). “Design, construction, and instrumentation of the 2006 test track structural study.” Rep. No. 09-01, National Center for Asphalt Technology (NCAT), Auburn, Ala.
Timm, D. H., and Priest, A. L. (2006). “Material properties of the 2003 NCAT Test Track structural study.” Rep. No. 06-01, National Center for Asphalt Technology, Auburn, Ala.
Timm, D. H., Priest, A. L., and McEwen, T. V. (2004). “Design and instrumentation of the structural pavement experiment at the NCAT test track.” Rep. No. 04-01, National Center for Asphalt Technology (NCAT), Auburn, Ala.
Van Wyk, A., Yoder, E. J., and Wood, L. E. (1983). “Determination of structural equivalency factors of recycled layers by using field data.” Transp. Res. Rec., 898, 122–132.
Von Quintus, H. L. (2007). “Evaluation of procedure to assign structural layer coefficients for use in flexible pavement design.” Rep. No. KS-07-9, Kansas Dept. of Transportation, Topeka, Kan.
Willis, J. R., and Timm, D. H. (2006). “Forensic investigation of a rich bottom pavement.” Rep. No. 06-04, National Center for Asphalt Technology (NCAT), Auburn, Ala.
Information & Authors
Information
Published In
Copyright
© 2011 ASCE.
History
Received: Sep 25, 2009
Accepted: May 11, 2010
Published online: Jun 5, 2010
Published in print: Jan 2011
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.