Evaluation of fatigue performance of asphalt mastics composed of nano hydrated lime filler

The present study evaluates the impacts of Nano hydrated lime filler (NHL) on fatigue damage potential of asphalt mastic and a comparative analysis with hydrated lime filler (HL). The study utilizes a control grade AC-30 binder with basalt (B), HL, and NHL fillers for production of asphalt mastic specimen. The dosages of HL and NHL fillers were selected as 0%, 5%, 10%, 15% and 20% by mass of AC-30 binder, and dosage of B filler were varied accordingly to maintain a particular filler to binder (f/b) ratio (0.6, 0.8, 1.0, 1.2, as per Superpave). A total of 36 different filler combinations (B, B-HL and B-NHL) were produced for all f/b ratios (0.6 to 1.2). The fatigue behavior of asphalt mastic at intermediate temperature (25 degrees C) was evaluated using the Temperature sweep and Linear amplitude sweep (LAS) test. Overall research outcomes infer that the reduction in the size of HL (NHL) fillers have a useful contribution to the fatigue damage potential of asphalt mastic. The Superpave fatigue factor and fatigue cycle parameter imply that both HL and NHL filler can enhance the resistance ability to withstand the fatigue damage of asphalt mastic. Besides, asphalt mastic composed of B-NHL filler can be less susceptible to higher degree of strain and hence, exhibited improved elastic properties than B-HL filler. Additionally, asphalt mastic composed of a lower percentage of NHL filler showed better resistance to intermediate temperature failure (fatigue damage) over mastic composed of a higher percentage of HL filler. On the contrary, 0.6-0.9f/b ratio was found to be suitable to achieve better performance of asphalt mastic considering stiffening effect and fatigue damage properties. (C) 2020 Elsevier Ltd. All rights reserved.