Study on the Effect of Surfactants on the Performance of Diluted Asphalt and Normal Temperature Mixture

Abstract

To explore the influence of surfactants on the performance of diluted asphalt and its mixture, a mixture of heavy oil viscosity reducers AMS and Span80 was added to diluted asphalt and the influences of the surfactants on the mixing and compaction of the diluted asphalt mixture were investigated through tests of the viscosity–temperature relationship, surface contact angle, mixing adhesion rate, and compaction characteristics. The experimental results show that (1) the mixed oil-soluble surfactant can significantly reduce the surface tension of the asphalt–aggregate interface and reduce the viscosity of the diluted asphalt, in which the influence on the interface is dominant. The addition of the mixed surfactant can ensure the mixing effect of the mixture under the condition of reducing the diesel consumption. (2) The addition of the mixed surfactant can reduce the viscosity of the diluted asphalt and has a significant effect on improving the construction workability of the diluted asphalt. It can significantly change the liquid–solid interfacial tension between the asphalt and the aggregate and make the asphalt mixture still achieve good construction performance under the condition of reducing the content of dilutant. (3) The addition of the mixed surfactant can make asphalt spread better on the aggregate surface, reduce resistance, and is easier for paving. (4) During the compaction process, the addition of the mixed surfactant can have a lubricating effect between the asphalt and the aggregate, make the final compactness of the diluted asphalt mixture greater, improve the wetting and paving ability of the asphalt on the aggregate surface, improve the mixing uniformity of the mixture, and make it easier for paving and compaction. (5) At the surfactant dosage of 1.0%–1.5%, the improvement of the paving and compaction characteristics of the diluted asphalt mixture can achieve the effect of adding 4%–6% of diesel oil, the 1.0%–1.5% mixed surfactant can replace 4%–6% of diesel dilutant, so that the mixture can achieve the same mixing uniformity and compacting performance.