Volume 35, Issue 3 (May 2007)
Bitumen Surface Energy Characterization by
Modern surface energy theory has been identified in recent years as an attractive tool by which to select compatible bitumen-aggregate combinations. In addition, this approach offers the potential to quantitatively assess moisture susceptibility of these material combinations. The success of implementing this technology depends on the availability of techniques that allow efficient and reliable surface energy characterization of the materials under consideration. This paper focuses on bitumen surface energy characterization employing inverse gas chromatography (IGC). The authors report detail column preparation and test methodologies, and provide a precision statement for this technique. Analysis procedures and results presented demonstrate successful application of this technique with modern thermodynamic theory to acquire bitumen surface energy components. The technique allows testing at different temperatures and results are in agreement with conceptual and theoretical expectations. Surface energies derived from IGC compare reasonably well with mechanical surface tension values from the literature. Results suggest that surface energies do not vary considerably between different bitumen types, indicative of the controlling role of aggregate type in bitumen-aggregate adhesion.