Impact of Nonlinear Elastic Behavior of Foamed Asphalt Stabilized Mixes on Pavement Structural Performance

Abstract

The mechanical behavior of cold recycled asphalt mixtures (CRAM) is influenced by its composition and limited studies have focused on exploration of nonlinear elastic behavior of CRAM. This study evaluates the effect of the nonlinear elastic properties of a CRAM as base course material on pavement structure using KENLAYER and multilayered elastic analysis (análise elástica de múltiplas camadas, or AEMC) simulations. The results indicate that the pavement structure and the active filler type have significant impact on the deflection and stresses within the pavement structure. Besides, considering the CRAM as nonlinear elastic material reduces the horizontal strains within the CRAM layer and the vertical stresses on top of the underlying layer as compared to the linear elastic scenario. Pezo’s model better characterizes the CRAM’s nonlinear elastic behavior compared to other models. Even though a small correspondence was observed between model predicted strain values and in situ measured data, the present study suggests that the higher bearing capacity of the CRAM layer in the nonlinear elastic scenario can lead to an improved pavement load capacity with a thinner structure resulting in lower construction costs.