Hma Dynamic Modulus Predictive Models (a Review)

Garcia, Gabriel; Thompson, Marshall

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https://hdl.handle.net/2142/46009 Copy

Description

Title

Hma Dynamic Modulus Predictive Models (a Review)

Author(s)

• Garcia, Gabriel
• Thompson, Marshall

Issue Date

2007-01

Keyword(s)

HMA modulus, hot mix asphalt, HMA modulus predictive models

Abstract

The most important hot-mix asphalt (HMA) property influencing the structural response of a flexible pavement is the HMA modulus (EHMA). Dynamic modulus concepts are reviewed. The construction of master curves for HMA mixtures is presented. The procedures are based on the fitting of a sigmoidal function. Two IE*I predictive equations are presented. The Witczak, as proposed in the new AASHTO 2002 Design Guide, and the Hirsch model. In general, both appear to be in good agreement and have similar accuracy. The Witczak predictive equation requires eight input parameters. This information is normally available from material specifications or volumetric design of the mixture. The master curve for IE*I can be developed directly by using the binder A and VTS parameters in the viscosity components of the equation. The Hirsch model needs only three input parameters, which are available from the routine Superpave mix design process. To build the IE*I master curve, a master curve for IG*Ibinder has to be developed to take into account the effect of temperature and frequency. This can be done with data obtained from Dynamic Shear Rheometer tests. Several studies are presented where the dynamic modulus predictive models are evaluated. The studies used different binders and represent typical mixtures used by different agencies. The results clearly confirm the good agreement and similar accuracy between the Witczak equation and the Hirsch model and between these models and dynamic modulus obtained from laboratory tests. In general, it is concluded that both predictive models generate sufficiently accurate and reasonable dynamic modulus estimates adequate for use in mechanistic-empirical design, at least for broad range of binders and mixtures studied.

Series/Report Name or Number

FHWA-ICT-07-005

ISSN

0197-9191

Type of Resource

text

Language

en

Permalink

http://hdl.handle.net/2142/46009

Sponsor(s)/Grant Number(s)

Illinois Department of Transportation ICT-R39

Copyright and License Information

No restrictions. This document is available to the public through the National Technical Information Service, Springfield, Virginia 22161

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