不同类型超薄层沥青混合料的水稳定性研究

Study of Water Stability of Different Asphalt Mixtures for Ultra-Thin Surfacing Layer

采用浸水车辙试验和冻融劈裂试验分别评价了Type-B（美国级配）、改良型SMA-10、OGFC-10这3种级配和SBS改性沥青、普通沥青＋8%抗车辙剂和高黏弹沥青3种结合料组成的9种超薄层沥青混合料的水稳定性。试验结果表明：有5种超薄层沥青混合料,即Type-B SBS改性沥青混合料、改良型SMA-10 SBS改性沥青混合料、Type-B高黏弹沥青混合料、改良型SMA-10高黏弹沥青和OGFC-10高黏弹沥青混合料满足现有规范对水稳定性的要求,其中改良型SMA-10高黏弹沥青混合料的综合性能最优,其条件前后的车辙动稳定度不仅分别是其他8种混合料的2.0～4.5倍和2.0～4.7倍。推荐该混合料用于重要的城市主干道、高速公路或重交通道路路面的预防性养护或维修。

By performing immersion rutting test and freeze-thaw splitting test,the water stability of nine different asphalt mixtures for ultra-thin surfacing layer was studied. The said nine asphalt mixtures were made respectively by three gradations（ namely Type-B with USA gradation,improved SMA-10 and OGFC-10） and with three binders（ namely SBS modified asphalt,common asphalt ＋ 8% anti-rutting agent and highly viscoelastic asphalt）. The test results show that five types of asphalt mixture for ultra-thin surfacing layer（ namely Type-B SBS modified asphalt mixture,improved SMA-10 SBS modified asphalt mixture,Type-B highly viscoelastic asphalt mixture,improved SMA-10 highly viscoelastic asphalt mixture and OGFC-10 highly viscoelastic asphalt mixture） meet China＇s prevailing specification for water stability of asphalt mixtures. Among them the improved SMA-10 highly viscoelastic asphalt mixture demonstrated optimal general performance with both rut dynamic stability and the immersion rutting dynamic stability 2. 0 ～ 4. 5 times and 2. 0 ～ 4. 7 times that of other eight mixtures and is thus recommended for use in pavement protective maintenance or repair of key urban artery,expressway or road of heavy traffic.