沥青老化及再生对自愈合性能的影响

Influence of Asphalt Aging and Regeneration on Self-healing Performance

摘要:

通过动态剪切流变仪（DSR）进行“疲劳-愈合-疲劳”试验，分析原样沥青、老化沥青及再生沥青在不同间歇时间下的自愈合性能，并结合红外光谱分析沥青老化、再生过程中官能团与自愈合性能的相关性.结果表明：老化过程中沥青发生了氧化反应，羰基和亚砜基官能团指数增大，极性氧化物含量增加，最终导致自愈合性能降低；添加5%Y型再生剂后沥青自愈合性能明显恢复，经旋转薄膜烘箱老化85、170、340 min的70#基质沥青再生后平均愈合指数恢复至70#基质沥青的100.9%、96.4%、63.2%，愈合速率分别恢复至基质沥青的89.7%、94.7%、40.7%，3种再生剂中Y型再生剂效果最好；沥青自愈合参数与亚砜基、羰基官能团指数线性相关性良好.

Abstract:

The self-healing properties of as-received asphalt， aged asphalt and recycled asphalt at different intermittent times were analyzed by dynamic shear rheometer （DSR） for “fatigue-healing-fatigue” test. The correlation between functional groups and self-healing properties during the aging and regeneration of asphalt was analyzed by infrared spectroscopy. The result shows during the aging process， the asphalt undergoes an oxidation reaction， the carbonyl and sulfoxide functional group indices increase， and the polar oxide content increases， which eventually leads to a decrease in self-healing performance. The self-healing performance of asphalt recovered obviously after adding 5% Y regenerant. The average healing index of 70# base asphalt aged 85， 170， 340 min in a rotary film oven was restored to 100.9%， 96.4%， 63.2% of that of 70# base asphalt. The self-healing rate recovered to 89.7%， 94.7%， 40.7% of the base asphalt， respectively. Among the three regenerants， the Y regenerant has the best effect； the self-healing parameters of asphalt have a good linear correlation with the indices of sulfoxide and carbonyl functional groups.