Sensitivity analysis of flexible pavement dimensioning using AASHTO (1993) Method. Part II: Effect of objective variables

Abstract

This is the second part of a study that conducted a sensitivity analysis of design variables of the American Association of State Highway and Transportation Officials - AASHTO (1993) in order to evaluate their influence in the dimensioning of flexible pavements. Just as was mentioned in Part I, the authors of this paper have found that design variables can be classified in two groups named “objective” and “subjective”. When these variables are defined by the designer, a high degree of variability may be present. The influence of subjective variables was presented in Part I. This paper (named Part II) shows the influence of objective variables (subgrade and traffic). As a general conclusion, the paper reports that thickness in the asphalt layer of a flexible pavement structure may increase approximately between 1.23 and 1.85, depending on the way in which the designer estimates objective variables. This could have an impact in structure costs that could vary between 1.13 and 1.5 times.