Gradation Design and Parameter Determination of Warm-Mix-Agent-Modified Asphalt Mixture.

ABSTRACT

In order to make up for inadequacies such as high energy cost in the production process and quantities of waste gas and dust release of hot-mix asphalt (HMA), warm-mix asphalt (WMA) has been developed. In this paper, the preparation process of WMA mixture is simply introduced. According to the experimental approach of asphalt binder and asphalt mixture, EC-120 is preliminarily selected as a follow-up research object after a rheological property test and a viscosity test of five kinds of warm-mix-agent-modified asphalts combined with cost analysis. A target mix proportion of SBS~AC-16 is designed, and then through the orthogonal design of the four parameters of the Marshall test of WMA mixture, such as mixing temperature, warm-mix-agent content, compaction blows, and mixing time, the best Marshall test parameters are obtained. The results show that the best parameters are 145 °C of mixing temperature, 3% of warm-mix-agent content, 75 compaction times, and 90 s of mixing time. This study can provide technical support and reference for the construction of WMA pavement in China.