既有沥青路面中面层高温性能发展规律试验分析

Experiment and Analysis on the Development Law of High Temperature Performance of Existing Asphalt Pavement

为了研究既有沥青路面中面层高温性能发展规律,文中建立了路面分层结构高温性能试验方法并提出了高温性能分级标准,针对车辙变形提出了分层结构变形率指标,选取典型半刚性基层沥青路面开展了现场取芯、变形率测量及高温性能试验研究。结果表明,分层高温性能试验方法能够有效评价既有路面分层结构的高温性能。中面层高温性能呈先增强后衰减的发展规律,且当现场车辙深度超过15mm时,其高温性能开始发生衰减,对应的中面层变形率分别为普通沥青混合料约11%、改性沥青混合料约6%。研究结论可以为既有路面高温性能评价提供支撑,为中面层养护时机和方案的确定提供依据。

To study the high temperature performance of intermediate surface layer of existing asphalt pavement,laboratory experiments and grading criteria are proposed in this paper.Deformation ratio of layered structure is adopted to evaluate rutting deformation.Typical asphalt pavements with semi-rigid base is studied by coring,deformation ratio measurement and high temperature experiments.It turns out that layered high temperature performance experiment can effectively evaluate the layered high temperature performance of existing asphalt pavement.The high temperature performance of intermediate surface layer shows a pattern of decreasing after increasing.When the rutting depth is over 15 mm,its high temperature performance starts to decrease.The corresponding deformation ratio of intermediate surface layer is 11%for normal asphalt mixture and 6%for modified asphalt mixture.This study can provide support for the evaluation of high temperature performance of existing pavement and determination of maintenance time and plan for intermediate surface layer.