Department of Civil Engineering, Braunschweig Pavement Engineering Centre (ISBS), Technische Universität Braunschweig, 38106, Braunschweig, Germany.
Department of Civil & Environmental Engineering, University of Alaska Fairbanks, 99775, Alaska, US.
Environ Sci Pollut Res Int. 2019 Dec;26(35):35620-35628. doi: 10.1007/s11356-019-05970-w. Epub 2019 Jul 24.
In this paper, the possibility of using different amounts of re-recycled (repeated recycled) Reclaimed Asphalt Pavement (RAP) in the asphalt mixture was experimentally investigated. First, a single virgin mixture was prepared and artificially aged to simulate the first generation of RAP to be used for designing the first generation of recycled mixtures. Next, the recycled mixtures were further aged to obtain a second generation of RAP to be mixed for preparing the second generation of recycled mixtures with and without the contribution of a rejuvenator. The fatigue behavior and low-temperature properties of all asphalt mixtures were experimentally investigated based on the cylindrical indirect tensile test (CIDT), Bending Beam Rheometer (BBR) mixture creep stiffness tests, and Semi-Circular Bending (SCB) fracture tests, respectively. Results indicate that re-recycled materials designed with and without rejuvenator show inferior fatigue behavior with respect to the first generation of recycled mixtures while exhibiting better performance than the virgin material. Meanwhile, poorer low-temperature creep properties were observed for the mixture prepared with recycled and re-recycled RAP. Fracture properties comparable with those of the virgin material were obtained only for re-recycled mixtures designed with rejuvenator. The present experimental work provides evidence on the possibility of using re-recycled RAP up to 40% when rejuvenators are included in the mix design.
本文通过实验研究了在沥青混合料中使用不同量再利用（重复回收）的再生沥青路面材料（RAP）的可能性。首先，制备了单一的新拌混合料，并对其进行人工老化，以模拟第一代 RAP 用于设计第一代再生混合料。接下来，对再生混合料进行进一步老化，以获得第二代 RAP，用于制备有和没有再生剂贡献的第二代再生混合料。分别基于圆柱状间接拉伸试验（CIDT）、弯曲梁流变仪（BBR）混合料蠕变劲度试验和半圆弯曲（SCB）断裂试验，对所有沥青混合料的疲劳性能和低温性能进行了实验研究。结果表明，与第一代再生混合料相比，设计中使用和不使用再生剂的再回收材料表现出较差的疲劳性能，但表现优于原始材料。同时，用回收和再回收 RAP 制备的混合料的低温蠕变性能较差。只有在再生剂被包含在混合料设计中的情况下，再回收混合物才能获得与原始材料相当的断裂性能。本实验工作为在包含再生剂的情况下，使用高达 40%的再回收 RAP 提供了可能性的证据。
