Influence of the mixing time on the anti-freezing performance of chloride-based asphalt mixtures

Abstract The performance of anti-freezing chloride-based asphalt mixtures is affected by the mixing time after the introduction of the anti-freezing component. This study establishes a mathematical model for the mixing uniformity in an agitator to optimize the mixing time and provide the best possible performance. Using this model, the mixing time required to ensure that the anti-freezing particles are uniformly dispersed in the asphalt mixture, but not evenly coated with asphalt, is determined. Combined with experiments, the results show that if the mixing time after the addition of the anti-freezing material is too long, the asphalt film on the particles will be too thick to release the particles and the anti-freezing performance will be degraded. Additionally, a mixing time that is too short will not fully disperse the anti-freezing material, also resulting in degradation of the anti-freezing effect. These restrictions provide a mixing time window that provides optimal performance. For a frequently used agitator with a rotational speed of 65 rpm, the recommended mixing time is no less than 30 s for a filling rate of 55%, and the ideal mixing time window is found to be 10–15 s.