A good quality bitumen emulsion is a key prerequisite for a bitumen emulsion material with good performance. However, current evaluation methods of bitumen emulsion cannot distinguish the quality of bitumen emulsions with the similar grade of chemical stability but different bitumen particles size distribution. The maximum packing fraction of bitumen particles (ϕ_m) formed during drying, which affects the chemical stability, drying process and film properties of emulsion, is firstly proposed to evaluate the quality of different bitumen emulsions. Then, the mechanism influencing the ϕ_m of bitumen emulsions is discussed. Results indicate that although the same emulsifier type and dosage are used to produce bitumen emulsions, the ϕ_m of different bitumen emulsions can still differ greatly if their particle size distributions are different. The ϕ_m of bitumen emulsion is related to the motion ability of bitumen particles in emulsion due to particle Brownian motion, which is mainly dominated by the bitumen particle size and emulsion viscosity. The smaller bitumen particle size and emulsion viscosity can lead to a higher ϕ_m. Based on the ϕ_m results of bitumen emulsions, an empirical prediction model relating ϕ_m to the essential properties of bitumen emulsion (bitumen particle size and emulsion viscosity) is established. The empirical model can give a good quantitative relation of ϕ_m with the two essential properties of bitumen emulsion. It can be used to rapidly judge the quality of bitumen emulsion and help to quantitatively understand the effect of bitumen particle size and emulsion viscosity on the quality of bitumen emulsion.

优质的沥青乳液是沥青乳液材料具有良好性能的关键先决条件。然而，目前的沥​​青乳液评价方法无法区分化学稳定性等级相似但沥青粒径分布不同的沥青乳液质量。首次提出了干燥过程中形成的沥青颗粒的最大堆积率( ϕ _m )，它影响乳液的化学稳定性、干燥过程和成膜性能，用于评价不同沥青乳液的质量。然后，讨论了影响沥青乳液φ _m的机制。结果表明，尽管使用相同的乳化剂类型和剂量生产沥青乳液，φ _m如果粒径分布不同，不同沥青乳液的性能仍然会有很大差异。沥青乳液的φ _m与沥青颗粒在乳液中由于颗粒布朗运动而产生的运动能力有关，主要由沥青粒径和乳液粘度决定。较小的沥青粒度和乳液粘度可导致较高的ϕ _m。根据沥青乳液的ϕ _m结果，建立了将ϕ _m与沥青乳液的基本性质（沥青粒度和乳液粘度）相关联的经验预测模型。经验模型可以给出ϕ _m的良好定量关系具有沥青乳液的两个基本特性。可用于快速判断乳化沥青质量，有助于定量了解沥青粒径和乳化粘度对乳化沥青质量的影响。