Fundamental Characterization of Louisiana HMA Mixtures for the 2002 Mechanistic-Empirical Design Guide
The main objective of this research was to develop a catalog for dynamic modulus values inputs in the 2002 Empirical and Mechanistic Guide for Design of New and Rehabilitated Pavement Structures (2002 M-E Design Guide) and to examine the permanent deformation characteristics of Louisiana hot mix asphalt (HMA) mixtures based on four laboratory tests, namely dynamic modulus |E*|, flow number, flow time and hamburg wheel tracker test. In addition, the sensitivity of rut prediction from the 2002 M-E Design Guide, using the dynamic modulus |E*| test results was evaluated and the Witczak and Hirsch models were also evaluated, for the prediction of dynamic modulus |E*| values for the mixtures considered. The dynamic modulus |E*| values, obtained from axial and indirect tension mode (IDT) mode of testing were also compared. Fifteen plant produced HMA mixtures designed for low, medium and high traffic levels were selected in this study. A catalog for dynamic modulus inputs in the 2002 Design Guide was developed for mixtures designed for low, medium and high traffic. Test results indicated that |E*| test results were sensitive to the nominal maximum aggregate size (NMAS) in HMA mixture. Larger aggregates combined with recycled asphalt (RAP) tended to have high |E*| values at high temperatures. The predicted rut depths from the 2002 M-E Design Guide followed similar trend as exhibited in the dynamic modulus |E*| test results at high temperatures. Both the Witczak and Hirsch models could predict the dynamic modulus |E*| values within a reasonable reliability. It was found that 73.3 percent of the dynamic modulus |E*| test results obtained from axial and indirect tension mode (IDT) were not statistically different.
Advisor:Louay Mohammad; John B. Metcalf; Radhey Sharma
School:Louisiana State University in Shreveport
School Location:USA - Louisiana
Source Type:Master's Thesis
Keywords:civil environmental engineering
Date of Publication:07/18/2006