Determination of the optimum binder content of warm mix asphalt incorporating Rediset using response surface method

This paper presents the effects of compaction temperatures (110–140 °C), Rediset contents (1–3%) and asphalt binder contents (4–6%) on the volumetric and strength properties of warm mix asphalt to optimize the binder content (OBC). For this purpose, an experimental matrix was planned based on the central composite design for three factors: Rediset content, compaction temperature and asphalt binder content. In addition, the volumetric and strength behavior of the samples were analyzed using response surface method, while the OBC was obtained from the results. The results showed that the maximum variation of the OBC for all cases is 0.25% and the OBC of warm mix asphalt compacted at high temperature is slightly higher than the OBC of warm mix asphalt compacted at lower temperature. It was also found that the OBC can be easily determined for a defined condition by using several factors simultaneously (for example binder content incorporating compaction temperature and additive content) and their relationships with strength and volumetric responses by using response surface method.