Influence of Additives on the Rheological Behavior of Asphalt Binder

Abstract

Asphalt cement practices ageing process through its service life due to the variation in temperature on the daily and mounthly bases. The asphalt binder exhibit losses in its flexibility due to the losses in the volatiles of its structure. It was felt that the implication of additives can enhance the quality of the binder and extend its service life. In the present investigation, two types of asphalt binder with penetration grade (60-70 and 40-50) were digested with micro size additive (Fly ash, and hydrated lime) and nano size additive (Fumed silica and silica fumes). The treated binders were subjected to rheological properties determination. The penetration viscosity number decreased by (2.8, 0.3, 1.4, and 1.4%) for binders 40-70 and (1.7, 1.2, 2.1, and 0.6%) for binders treated with fly ash, fumed silica, silica fumes, and hydrated lime, respectively. The viscosity of asphalt binder (40-50) rises by 5.8, 33.4, 54.4, and 43.6%, and that of fly ash, fumed silica, silica fumes, and hydrated lime (60-70) rises by (102.5, 135.5, 112, and 12%), respectively. For (40-50) and (60-70) binders, the creep stiffness increases by (5, 25, 35, and 32.5) % and (6.2, 12.5, 18.7, and 25) % when fly ash, fumed silica, silica fumes, and hydrated lime were implemented. It can be concluded that implementation of Nano size additives exhibits lower temperature susceptibility when compared with Micro size additives