Experimental Procedures for Evaluating Asphalt Mix Stability Using the Superpave Gyratory Compactor

Abstract

In the Superpave gyratory compactor (SGC), the compaction process occurs under a vertical pressure at the top of the specimen and shear displacement induced by the gyratory movement of the compactor. The response of the mix to the compaction effort depends on its shear resistance, which is a function of many factors including aggregate properties, asphalt content, and asphalt grade. A new approach that consists of experimental and analysis procedures is developed in order to evaluate asphalt mix stability during the compaction process. The sensitivity of the developed stability parameters to changes in mix components is evaluated by analyzing asphalt mixes that differ in their nominal maximum aggregate size, aggregate gradation, source of aggregate, percent natural sand, asphalt content, and asphalt grade. The results show that the developed energy index is sensitive to the percent of asphalt content, percent natural sand, and aggregate type. For the covering abstract see ITRD E118503.