针对不同多聚磷酸改性沥青胶结料进行了常规高温性能试验和Superpave高温性能试验,得到了不同的高温性能评价指标,并对比分析了沥青胶结料高温性能评价指标之间的关系.采用改进后的车辙试验验证了沥青混合料的高温性能,研究了沥青胶结料与混合料高温性能之间的相关性.通过差示扫描量热法(DSC)试验分析了多聚磷酸改性沥青以及SBS复配多聚磷酸改性沥青的改性机理.结果表明:软化点和累积应变可以较准确地评价不同类型沥青胶结料的高温性能;掺加多聚磷酸可以减小基质沥青和SBS改性沥青的热流率,从而改善基质沥青和SBS改性沥青的热稳定性;累积应变可作为高弹改性沥青胶结料的较合理评价指标.
The conventional high temperature performance test and the Superpave high temperature pertormance test were carried out by using different modified asphalt binders, thus achieving different high temperature performance indexes. Then, the relationships between the indexes were discussed. Moreover, the high temperature performance of asphalt mixtures was verified by the improved rutting test, and the correlation between the high temperature per- formance of the asphalt binder and that of the asphalt mixture was investigated. Finally, the modification mecha- nisms of the polyphosphoric acid (PPA) -modified asphalt and the SBS compound PPA-modified asphalt were ana- lyzed by means of DSC. The results show that ( 1 ) the softening point and the accumulated strain can evaluate the high temperature performance of different types of asphalt binders more accurately ; (2) the addition of PPA can decrease the heat flow rates of both the matrix asphalt and the SBS-modified asphalt, thus improving their thermal stability ; and (3) the cumulative strain can be used as a reasonable evaluation index of high elastic modified asphalt binder.