超薄磨耗层高黏高弹沥青混合料性能研究

为给超薄磨耗层提供一种性能优良的沥青混合料，通过优化级配并以高黏高弹改性沥青为胶结料研制骨架密实型高黏高弹沥青混合料。借鉴SAC( stone asphalt concrete）级配设计方法，以8 mm为集料最大粒径，改变4.75 mm筛孔通过率得到骨架嵌挤程度不同的3种SAC-7级配。通过室内试验和控制变量的方法，分析级配、沥青用量、压实度、粉胶比等对骨架密实型高黏高弹沥青混合料路用性能影响。研究表明：当高黏高弹沥青混合料中粗集料嵌挤程度≥90%，油石比在7.3%～7.9%，粉胶比在0.8～1.2时，沥青混合料综合性能最优。采用SAC设计方法设计的高黏高弹沥青混合料应用于超薄磨耗层具有优良的路用性能，能够满足高等级道路养护需求。

Performance of ultra-thin wearing course with high-viscosity and high-elastic asphalt mixture

To provide a high performance asphalt mixture for the ultra-thin wearing course, a skeleton dense high viscosity and high elasticity asphalt mixture was developed by optimizing the grading and using high viscosity and high elasticity modified asphalt as the binder. According to stone asphalt concrete (SAC) gradation design method, three types of SAC-7 gradations with different skeleton structure were acquired by changing aggregate passage rate at sieve-size 4.75mm with 8mm as the maximum size aggregates. Through indoor experiments and variable control methods, the effects of different factors include coarse aggregate skeleton structure, asphalt content, compaction degree and filler-asphalt ratio on the road performance of asphalt mixture were investigated. The results show the whole quality is best when coarse aggregate skeleton structure is greater than or equal to 90%, with an oil stone ratio of 7.3% to 7.9%, and a filler-asphalt ratio of 0.8 to 1.2. The asphalt mixture designed according to SAC design method shows good road performance when used as ultra-thin wearing course material, which can meet the needs of high-grade road maintenance.