Project Summary
Asphalt-treated bases are often used in new pavements, the materials are available and low-cost, but there is little data on how these materials perform in cold regions. This study investigated four ATB types (hot asphalt, emulsion, foamed asphalt, and reclaimed asphalt pavement) popular for treating base course materials. The research team collected data on stiffness, fatigue, and permanent deformation characteristics under different temperatures. This study produced a detailed literature review, including information from ongoing research projects, to compile the latest information concerning ATB characterization. Also completed were resilient modulus tests of ATB material commonly used for Alaska's northern and central regions, as well as rutting tests using a Georgia Loaded Wheel Test apparatus. Researchers conducted resilient modulus tests on specimens of foamed asphalt-treated base material, fabricated in ADOT&PF labs, in all three Alaska regions, an additional test was performed in the central region using different binder contents and soaked conditions. Statistical analysis of the effects of aggregate properties on the resilient modulus were completed and incorporated into the finalized model. Study recommendations noted that based on the predicting equations for resilient modulus (MR), the moduli of treated base course materials can be calculated according to treatment technique, ambient temperature, aggregate properties, and binder content.