Characterizing Stress–Strain Relationships of Asphalt Treated Base

Abstract

In a flexible pavement, the base course is an essential component in that it supports the surface course and distributes traffic loads to the subbase and subgrade. Asphalt treatment is used on granular base course material to enhance the material’s properties and overcome its deficiencies. Due to its lower binder content and lower-quality granular material, asphalt treated base (ATB) exhibits a stress–strain relationship unlike either regular granular material or hot mix asphalt. Stress−strain relationship is the primary fundamental material property used for mechanistic-based pavement structural analysis and design. However, current guidance for choosing the parameter that characterizes the stress−strain relationship of ATB in pavement design is not clearly provided. This paper presents a study in which the stress−strain relationship of differing base materials, including three ATBs, a mixture of reclaimed asphalt pavement and granular material, and a typical granular base material, is compared and analyzed based on data measured from repeated triaxial compressive tests. The resilient modulus (