薄型沥青混凝土在BRT专用车道的应用研究

Application Study on BRT Special Lames of Thin Asphalt Concrete

薄型沥青混凝土是起源于上世纪80年代的新型路面材料,凭借其良好的抗滑、减噪、防水功能,在国外已经广泛使用,国内也得到初步的应用,薄型沥青混凝土主要运用于路面预防养护和旧路改建。本文针对快速公交系统(BRT)的运行特点和BRT专用车道的病害,借鉴国内外薄型沥青混凝土经验,提出采用SMA-13+RA抗车辙剂作为BRT车道面层材料,并确定了该级配混合料的最佳油石比。采用有限元方法分析了SMA-13+RA抗车辙剂作为BRT车道面层沥青路面结构的应力状态,通过室内浸水马歇尔试验和冻融劈裂试验以及车辙试验等检测了该混合料的路用性能,并运用到实际BRT专用车道改建工程中。路用性能的实地检测表明该混合料满足规范要求,为以后BRT车道的改扩建提供了参考。

Thin asphalt concrete pavement is new-type of materials which originated in the 1980s. It has been widely used in foreign due to its good performance, such as anti-skating, noise reduction, waterproof. It also gets preliminary application in civil. Thin asphalt concrete has been widely used in pavement preventive maintenance and old road reconstruction. Consider the operation characteristics of the rapid transit system （BRT） and the disease of BRT special lanes, SMA-13 ＋ Anti-Rut agent RA as surface course using in BRT special lanes is proposed and the best proportion is confirmed, which refer to the domestic and foreign experiences. Stresses of pavement with flexible base of SMA- 13 ＋ Anti-Rut agent RA as surface course were calculated and compared by finite element method. The properties of the mixture are verified through a series of indoor tests, such as Retain Marshall test, freeze-thaw splitting test and rutting test. The mixture has been applied to actual BRT special lanes in the reconstruction project. The field performance detections conclude that the mixture satisfied the standard requirement, which provides references for later BRT driveway reconstruction.