基于加速加载的SMA沥青道面轮辙特性分析

Analysis of the SMA Asphalt Pavement Rutting Characteristics Based on Accelerated Pavement Testing

对某军用机场试验段两种SMA道面结构在60℃条件下,展开加速加载试验,研究SMA道面轮辙变形特性。通过两种结构道面轮辙变形发展特性对比分析,探究环氧沥青道面结构的轮辙变形值、变形速率、变形面积及隆起变形比例。试验结果表明,由于不同下卧层对沥青面层的应力状态影响,致使两种道面结构轮辙特性及发展规律明显不同;两种道面结构的轮辙发展可分为3个阶段,但SMA复合道面较SMA半刚性基层沥青道面变形发展速度和数值都小。SMA半刚性基层沥青道面车辙凹陷面积始终都大于隆起面积,而SMA复合道面在加载前期,凹陷面积大于隆起面积,但加载到一定次数后隆起面积大于凹陷面积;隆起比例系数与道面结构有关,初期两种道面的隆起比例系数有所波动,但随后基本稳定。SMA半刚性基层沥青道面的隆起比例系数的最终的建议取0.45,而SMA复合道面的隆起比例系数的最终的建议取0.6。

Accelerated loading test was carried outto study SMA pavement rut deformation characteristics under the condition of 60 ℃ at a military airport test section in East China , which is two kinds of pavement structure. Rut deformation development characteristics of four kinds of pavement structures was contrastedand analyzed to explore the rut deformation value,deformation rate,deformation area and uplift deformation ratio of epoxy asphalt pavement structure. Test results show that rutting characteristics and law of development of two kinds of pavement structure has been caused by the different substratumof SMA pavement. Developing rutof two kinds of pavement structurecan be divided into three stages,but deformation development speed and the value of SMA composite asphalt pavement is small than SMA semi-rigid base asphalt pavement. SMA semi-rigid base asphalt pavement rutting sag area is always greater than uplift area, and SMA composite pavement rut sag area is greater than the uplift area in the early stage of the load, but uplift, area is greater thon the sag areaafter a certain number of times ; For two kinds of pavement,uplift ratio is fluctuant at the beginning of the load and is stable in the subsequent loading. The final uplift ratio of SMA semi-rigid base asphalt pavementis suggestedfor 0.45, while the final uplift ratio of SMA composite asphalt pavementis suggestedfor 0. 6.