To research workability of asphalt, an evaluation indicator of mixture workability-workability index was put forward and a tester of asphalt mixture workability index was developed. The workability of mixtures was tested at different rotation speeds of the tester, different graduation types of mixture aggregates and different hot and warm mixing conditions. Results indicated that the higher rotation speed, the smaller the workability index, thus the workability of mixtures was worst. With the rise of temperature, the difference of the workability caused by rotation speed become smaller. The larger maximum nominal sizes of aggregate were, the smaller workability index and the worse its workability were. With the rise of the temperature, the workability of mixture with smaller aggregate size become larger. The workability index of warm mix asphalt was the biggest, and its workability was best. The workability index of hot mix modified asphalt was the smallest,and its workability was worst. When the temperature was lower than 140 X. ,the workability index of hot mix asphalt was bigger than that of warm mix modified asphalt, and its workability is good. When the temperature was higher than 140 t ,the workability index of hot mix asphalt was commensurate with that of warm mix modified asphalt. The result idicated that, using the warm mixing tech-nology could improve the workability of modified asphall mixture and the deficiency of modified-asphalt-mixture road performances caused by temperature decreasing.%为了研究沥青混合料和易性,研发沥青混合料和易性指数测试仪,提出混合料和易性评价指标--和易性指数,分别测试在不同转速、不同级配类型、热拌及温拌条件下混合料和易性.结果表明:转速越大,和易性指数越小,表现出混合料和易性较差,随着试验温度升高,因转速造成的和易性差异减小;混合料公称最大粒径越大,其和易性指数越小,和易性越差,随着温度升高,粒径较小的混合料和易性提升幅度较大;基质沥青温拌混合料和易性指数最大,和易性最好,改性沥青热拌混合料和易性指数最小,和易性最差.当温度低于140℃时,基质沥青热拌混合料和易性指数较改性沥青温拌沥青混合料大,和易性好.当温度高于140℃时,基质沥青热拌混合料和易性指数与改性沥青温拌混合料相当,说明通过温拌技术,可使得改性沥青混合料和易性增加,可弥补因温度降低而造成的改性沥青混合料路用性能降低之不足.
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