HIGH PRESSURE LIQUID CHROMATOGRAPHY AS A METHOD OF MEASURING ASPHALT COMPOSITION

Abstract

The molecular size composition of asphalt as determined by high pressure liquid chromatography (HPLC) has been related to the performance of bituminous roadways in the state of Montana. HPLC and asphaltenes analyses have been used to define the characteristics of an asphalt which has shown satisfactory durability and longevity. These characteristics have been proposed as a model of high quality asphalt. HPLC has been used to characterize the the asphalts produced by each of Montana's refineries. It has also been used to follow the changes in the molecular size distribution which result from mixing with aggregate and with lime. These results suggest that the molecular size characteristics of asphalt may be engineered to more closely approach the model. It is also suggested that HPLC analysis may be valuable in designing pavement recycling projects. HPLC has been shown to be a more accurate measure of asphalt quality than asphaltenes content, penetration or ductility. (FHWA)