The degree of blending of reclaimed asphalt pavement (RAP) binder is profoundly influencing the performance of asphalt mixtures containing RAP. Hence, it is essential to know the amount of RAP binder mobilized into the mixture to produce more durable asphalt mixtures. However, understanding the factors affecting the degree of blending and quantifying the degree of blending is still an open problem for researchers. This study investigates the effect of several factors such as blending method, blending temperature, blending duration, and RAP content on the degree of blending using Fourier Transform Infrared Spectroscopy (FTIR) analysis of the extracted binder from mixtures. It is revealed that the blending method, blending temperature, and blending duration have a significant influence on the degree of blending. The study revealed that prolonged blending durations and elevated mixing temperatures could improve the degree of blending. The amount of RAP in the mixture has little or no influence on the degree of blending. Further, based on the results, a blending chart is developed to determine the degree of blending with regard to blending duration and blending temperature.

再生沥青路面（RAP）粘合剂的共混程度深刻影响着含有RAP的沥青混合物的性能。因此，至关重要的是，要知道动员到混合物中的RAP粘合剂的数量，以生产出更耐用的沥青混合物。但是，了解影响混合程度的因素并量化混合程度仍然是研究人员的未解决问题。本研究使用傅立叶变换红外光谱（FTIR）分析混合物中提取的粘合剂，研究了混合方法，混合温度，混合持续时间和RAP含量等因素对混合度的影响。结果表明，混合方法，混合温度和混合时间对混合程度有很大影响。研究表明，延长混合时间和提高混合温度可以提高混合度。混合物中RAP的量对混合程度几乎没有影响。此外，基于结果，开发混合图以确定关于混合持续时间和混合温度的混合程度。