Structural Performance Using Deflection Basin Parameters of Asphalt Pavements with Different Base Materials Under Heavy Traffic

Pavement deflection is generally obtained by means of Falling Weight Deflectometer (FWD) tests, which provide an evaluation of the structural behavior of highway constructions and indicate the evolution of pavement damage through time. This paper evaluated FWD data, backcalculated moduli, and deflection basin parameters (DBPs) (radius of curvature, area, structural curvature index, base damage index, and base curvature index) to analyze the structural performance of an experimental road pavement test section with four different asphalt pavement segments. The segments had different base layer materials, and they were constituted by one flexible structure (unbound granular base layer), one semi-rigid (cement-treated base layer), one cold recycled asphalt mixture layer stabilized with asphalt emulsion (CRAM-EM), and one cold recycled asphalt mixture layer stabilized with foamed asphalt (CRAM-AF). The field monitoring had eight surveys that included the evaluation of surface distresses and deflection measurements along 3 years of study. The backcalculated moduli of the asphalt layer, base, and remaining pavement structure presented an overall good correlation with the DBPs evaluated.