Porous hot mix asphalt (PHMA) allows runoff to infiltrate through the pavement. Cured carbon fiber composite materials (CCFCM)s from aerospace production lines were ground into three size groups (Fine, Medium, and Large) and reused as reinforcement agents for PHMA in comparison to commercial synthetic fiber. The Fine CCFCMs premixed with liquid asphalt binder performed the best to reinforce PHMA in terms of indirect tensile strength and cracking resistance at both 25C and 10C. The addition of fine CCFCMs and synthetic fibers reduced the porosity by 17% and infiltration rate by up to 20%, while both fibers showed to prevent drain down of asphalt binder at an elevated temperature. The PHMA reinforced with the Fine CCFCMs performed the best in rutting resistance. One of the main challenges associated with traditional impermeable pavement structures is runoff control.

Mix design of control PHMA Information is regarding the asphalt binder used in a study.  The target air void of the PHMA was 20% which was achieved by 75 gyration effort in the compactor. The minimum required infiltration rate is 254 cm/hr (100 in/hr) [14]. The mixing and compaction temperatures ranged from 164.4 to 170.6C, and 152.8–157.2C, respectively, based on the recommendation of the asphalt binder supplier, US Oil and Refining. The temperature-viscosity chart is shown in Fig. 1, provided in the Job Mix Formula.  Based on the surface area factor shown by others, the calculated surface area of this aggregate gradation is 2.24 m2/kg and the binder film thickness without considering binder absorption is 26.2 microns, based on 6%asphalt content by the weight of dry aggregate. The higher binder film thickness is designed in this PHMA is to provide better performance in terms of durability and resistance to raveling and aging.

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