SBS改性沥青回收影响因素及改进措施

Influence factors and improvement measures of recovery of SBS modified asphalt

为真实反映回收SBS改性沥青的性能,分析了现行离心抽提法和阿布森蒸馏法的不足及产生原因,设计了不同的对比试验,研究矿粉、三氯乙烯、蒸馏过程对新、旧改性沥青性状的影响,并提出相应的改进措施.研究结果表明:少量矿粉对改性沥青性能影响较小,采用高速离心机可消除矿粉的干扰;三氯乙烯对改性沥青性能影响较大,尤其是低温延度,而改性沥青相态结构与三氯乙烯无显著关系,提出采用真空干燥箱消除三氯乙烯影响;采用改进的方法回收新、旧改性沥青混合料中的改性沥青,性能变化较小,相态结构未发生显著变化,表明该方法可较为准确地评价回收改性沥青的性能.

To reflect the properties of SBS modified asphalt better,the shortcomings and corresponding reasons of current centrifugal extraction and Abson distillation are analyzed.Different comparative tests are conducted to study the effects of mineral filler,trichloroethylene and distillation process on the origin and aged modified asphalts;and the corresponding improvement measures are put forward.The results show that a small amount of mineral filler has a little influence on properties of modified asphalt;and the high-speed centrifuge can eliminate the influence.Trichloroethylene has a great influence on the properties of modified asphalt,especially low-temperature property;and the phase structure of modified asphalt has no relationship with trichloroethylene.The vacuum drying oven is proposed to eliminate the influence of trichloroethylene.The modified asphalts extracted from origin and aged modified asphalt mixtures have little change compared with the origin modified asphalt by the improvement recovery measures;and the phase structure is also not changed significantly,which eventually shows that the improvement recovery method can evaluate the properties of recycled modified asphalt accurately.