Characterization of emulsion bitumen stabilized aggregate base

Stabilization of road aggregate using emulsion bitumen is a common alternative when constructing and/or rehabilitating low volume pavements. The engineering behavior of the Emulsion Aggregate Mixture (EAM) is primarily influenced by aggregate gradation, properties of bitumen emulsion, environment temperature, and moisture content. In this study, a well-graded crushed limestone was treated with SS-1hp type anionic emulsion bitumen. Several laboratory tests including gradation, Atterberg limits and compaction, i.e. moisture-density, were conducted on the virgin as well as emulsion stabilized base aggregate. According to a special curing procedure that was followed, the level of moisture susceptibility could be adequately specified for the EAM samples. Performance tests, such as indirect tensile strength and permanent deformation, and a new advanced directional resilient modulus test were conducted to evaluate the engineering properties of dry and wet cured EAM and virgin aggregate specimens. The findings from this study indicated that emulsion stabilization could adequately improve the bearing capacity of the pavement base/subbase by increasing the strength and modulus properties and reducing the tendency to deform under applied traffic loading.