In this report, sensitivity analyses were conducted of the new AASHTO 2002 method for both flexible and rigid pavements, to understand its performance with respect to the various design parameters. To overcome these limitations AASHTO finally proposed the AASHTO 2002 design guide which is based on mechanistic empirical approach and serves to address the shortcomings and limitations of the earlier empirical design equations developed from the Road Tests. For example, the traffic loads and truck sizes have increased over the years, the AASHTO design equations were derived based on the climatic conditions present at the Road Tests site, and the issue of aging materials was not addressed in the design. The various editions of the AASHTO pavement design guide have served well for several decades nevertheless many serious limitations existed for their continued use as the nation's primary pavement design procedure. Knowledge gained from the parametric analysis of different sections using AASHTO 1993 and MEPDG is expected to be useful to pavement designers and others in implementation of the new MEPDG for future pavement design.Over the years pavement design has been based on empirical equations developed from the American Association of State Highway Transportation Officials (AASHTO) road tests. Cost comparisons of sections stabilized with different percentage and type of additives showed that CKD-stabilization provides economically low cost sections as compared to lime- and CFA-stabilized sections.

It is found that the design thickness is influenced by the type of soil, additive, selection of material property and design method. Specifically, comparisons were made for a range of different sections consisting of cementitious layers stabilized with different types and percentages of additives. The primary objective of the study presented in this paper is to develop design curves for performance prediction of stabilized layers and to compare semi-rigid flexible pavement designs between the empirical AASHTO 1993 and the mechanistic-empirical pavement design methodologies.

Flexible pavement design aashto example