醋酸类除冰盐侵蚀沥青混合料机理研究

Mechanism of acetate-based deicer eroding asphalt mixture

使用醋酸类除冰盐除冰雪后,沥青路面出现沥青软化、沥青膜剥落、混合料松散等新型病害而导致沥青路面耐久性下降.针对新型除冰盐侵蚀破坏沥青混合料问题,提出了以TSR/D作为技术指标的浸没间接拉伸试验方法(ITT),试验结果表明醋酸类除冰盐侵蚀破坏沥青混合料的程度与除冰盐溶液的浓度呈正相关性.研究同时从沥青软化及除冰盐溶液-沥青界面特性二个角度开展除冰盐溶液侵蚀机理试验分析.采用动力粘度试验研究沥青粘度变化规律,结果表明:沥青经过高浓度除冰盐溶液浸泡后,沥青粘度明显降低,浸泡溶液浓度越高、浸泡时间越长沥青软化现象越显著;采用核磁共振试验研究除冰盐溶液-沥青界面特性,结果表明,随着除冰盐浓度的增加,除冰盐溶液表面张力降低、除冰盐密度增加,除冰盐液滴渗入沥青膜内部的速度明显增加,进而加速沥青路面的损坏.

The use of new acetate-based deicer makes the durability deterioration of asphalt pavement. Ac- cording to new type deicer erosion asphalt mixture problem, the paper puts forward immersion tension test, which takes TSR/D as technical index. The results indicate that the erosion of deicer reduces asphalt mixture tension strength; and the degree of deterioration depends on concentration of deicer solutions. The paper studies mechanism of deicer erosion asphalt mixture through two different respects, including as- phalt softening and interracial properties between asphalt and deicer solution, which use viscosity test and nuclear magnetic resonance （NMR） separately. The viscosity of asphalt decreases through the long time immersion in deicer solutions. Concentration of solutions increasing, surfaeial tension decreases and densi- ty increasing, the lower surface and the higher density of solutions means that these will penetrate into the HMA pavement more rapidly than water.