ABSTRACT

The use of a reinforcing fibre in porous asphalt (PA) is a common practice to improve PA’s homogeneity and durability. This study developed a new type of fibre-shaped reinforcement element from cured carbon fibre composite materials (CCFCMs), which were collected from the waste stream of an aerospace manufacturing process. One control PA without CCFCMs and three PAs, which are reinforced by Fine CCFCMs, Medium CCFCMs, and re-refined Medium CCFCMs, were produced in a commercial asphalt plant and placed and compacted in the field. In-place and laboratory tests were performed to determine air voids, infiltration, and mechanical properties of PA lanes and field cores, respectively. The PA reinforced by the re-refined Medium CCFCMs exhibited the highest infiltration rate and the best ductility among these four PA mixtures. The laboratory performance results indicated that both compaction and binder draindown can influence the infiltration and mechanical performance of PA. In addition, the porosity is a more reliable parameter than air voids to correlate with water infiltration rates of PA specimens. A nuclear density gauge is highly recommended to use in the PA compaction process to monitor the in-place density and assure the hydraulic performance of PA lanes.

摘要

在多孔沥青 (PA) 中使用增强纤维是提高 PA 均匀性和耐久性的常用做法。本研究利用从航空航天制造过程的废物流中收集的固化碳纤维复合材料 (CCFCM) 开发了一种新型纤维状增强元件。一种不含 CCFCM 的对照 PA 和三种由细 CCFCM、中型 CCFCM 和再精制中型 CCFCM 增强的 PA 在商业沥青厂中生产，并在现场放置和压实。进行就地和实验室测试以分别确定 PA 通道和场核心的气孔、渗透和机械性能。在这四种 PA 混合物中，由重新精制的培养基 CCFCM 增强的 PA 表现出最高的渗透率和最好的延展性。实验室性能结果表明，压实和粘结剂排出都会影响 PA 的渗透和力学性能。此外，孔隙率是比气孔更可靠的参数，与 PA 样品的水渗透率相关。强烈建议在 PA 压实过程中使用核密度计来监测原位密度并确保 PA 车道的水力性能。