Yu Weixiao, Li Yun, Liang Zhipeng, Wu Jiaxi, Wang Sudi, Miao Yinghao
National Center for Materials Service Safety, University of Science and Technology Beijing, Beijing 100083, China.
Beijing Transportation Infrastructure Construction Project Management Center, Beijing 100053, China.
Materials (Basel). 2025 Apr 25;18(9):1953. doi: 10.3390/ma18091953.
Aggregates are the main material forming the skeleton structure of asphalt mixtures and are of great importance to resist external load for asphalt pavement. This study analyzed the packing characteristics and mechanical performance of aggregate blend to provide a reference for improving the bearing capacity of asphalt mixtures. The single-size, two-size, and multi-size aggregate blends were chosen to conduct the laboratory packing and California bearing ratio (CBR) tests. Six particle sizes were selected to design the single-size aggregate blends. Six size combinations were included and various mass ratios were considered for each size combination in the two-size aggregate blends. The multi-size aggregate blends were designed through the gradually filling method according to stone matrix asphalt with a nominal maximum particle size (NMPS) of 16 mm (SMA16) and dense asphalt concrete with an NMPS of 26.5 mm (AC25). The packing characteristics of the blends were quantified by the air voids and the percentage of contribution to the packing volume (). The mechanical performance of the blends was analyzed by the CBR value. The relationship between packing characteristics and mechanical performance was explored by data fitting. The results showed that the particle size and the size ratio have an effect on the packing characteristics and mechanical performance of aggregate blend. The smaller the particle size, the larger the air void of the blend. The blends composed of larger particles have better load bearing capacity than those composed of smaller particles. The larger the particle size ratio, the greater the air void of the blend and the weaker the load bearing capacity. The particles smaller than 1.18 mm and those smaller than 0.3 mm in AC25 mainly play a role in filling the voids and have little contribution to the load bearing. There is a certain correlation between the packing characteristics and mechanical performance of aggregate blend.
集料是形成沥青混合料骨架结构的主要材料，对沥青路面抵抗外部荷载具有重要意义。本研究分析了集料混合料的堆积特性和力学性能，为提高沥青混合料的承载能力提供参考。选择单粒径、双粒径和多粒径集料混合料进行室内堆积试验和加州承载比（CBR）试验。选择六种粒径设计单粒径集料混合料。双粒径集料混合料包含六种粒径组合，并考虑了每种粒径组合的不同质量比。根据公称最大粒径（NMPS）为16mm的SMA16（沥青玛蹄脂碎石混合料）和NMPS为26.5mm的AC25（密级配沥青混凝土），通过逐步填充法设计多粒径集料混合料。混合料的堆积特性通过空隙率和对堆积体积的贡献率（）来量化。混合料的力学性能通过CBR值进行分析。通过数据拟合探索堆积特性与力学性能之间的关系。结果表明，粒径和粒径比会影响集料混合料的堆积特性和力学性能。粒径越小，混合料的空隙率越大。由较大粒径颗粒组成的混合料比由较小粒径颗粒组成的混合料具有更好的承载能力。粒径比越大，混合料的空隙率越大，承载能力越弱。AC25中小于1.18mm和小于0.3mm的颗粒主要起填充空隙的作用，对承载能力贡献不大。集料混合料的堆积特性与力学性能之间存在一定的相关性。
