Study of Aging Characteristics of Recycled Asphalt Binders: Focusing on the Chemical Properties

Chui-Te Chiu ； Yi-Hsiang Chiu

《International Journal of Pavement Research and Technology》 1卷1期 (2008/01) Pp. 17-23

https://doi.org/10.6135/ijprt.org.tw/2008.1(1).17

並列摘要

After several years of service, the aromatic components in asphalt cement turn into asphaltenes, which result in stiffer, fragile and distressed pavements. In hot in-plant rlecycling operations, new binder (or recycling agent) and aggregate are mixed with reclaimed asphalt pavement (RAP) to minimize the negative effects of age hardening. As described in the literature, recycling agents should be highly aromatic to produce recycled pavement superior to original pavement. Many studies have been done studying physical properties and pavement performance of recycled asphalt mix, but rarely have they focused on the chemical properties. This study attempted to investigate the chemical components of recycled asphalt and their effects on recycled asphalt binder properties. The effectiveness of using different recycling agents in the recycled asphalt mixes was also evaluated. The results indicated that conventional AC-10 could be effective in softening severely aged RAP to produce asphalt binder with viscosity in the range of paving asphalt. However, recycled asphalt mixes with AC-10 as a rejuvenator show not only higher asphaltenes but also higher polar aromatics and lower naphthene aromatics. The two recycling agents, RA75 and RA250, however, showed beneficial effects in terms of both viscosity and chemical components. An asphalt binder aging index, Corbett Aging Index, based on calculations of asphaltenes and naphthene aromatics, is proposed as an effective parameter to sensitively detect aging severity of different recycled mixes.

並列關鍵字

Chemical components ； Corbett method ； Recycled hot-mix asphalt ； Viscosity.