多级矿料-沥青体系的颗粒特性、界面效应及迁移行为研究进展

沥青混合料是多级多相颗粒性材料，其复杂的颗粒特征、界面效应和迁移行为决定了离析特性、压实效果与力学响应。为了解析沥青混合料的微细观作用机理，为混合料组成优化设计、施工控制及性能预测提供理论基础，进而提升沥青路面的耐久性，综述了国内外学者在矿料-沥青体系的研究成果，并将摊铺、压实、服役阶段的沥青混合料分别看作不同状态及迁移自由度的矿料-沥青体系。首先，针对矿料体系的颗粒特性，分析了颗粒几何形态以及尺寸效应对沥青混合料性能的影响，给出了多级矿料复合几何特征表征方法。其次，针对松散态的矿料-沥青体系，梳理了矿料颗粒体系的接触摩擦特性、界面交互作用等细观特征，介绍了沥青混合料的离析行为评价方法，分析了颗粒迁移行为对离析倾向的影响，并讨论了离析形成机理；针对沥青混合料的压实过程，描述了动态压实特性与颗粒的迁移行为，分析了矿料几何特征、矿料-沥青界面效应对颗粒迁移行为的影响，从内部颗粒迁移角度讨论了沥青混合料的压实过程；针对压实成型的沥青混合料，介绍了矿料-沥青体系的颗粒迁移行为，并分析了颗粒微迁移特性对沥青混合料力学强度的影响。最后，将运输摊铺过程的松散态、压实过程中的错动态、服役过程中的成型态...

Research Advances of Aggregate Characteristics,Interface Effect,and Migration Behaviors of Multi-level Aggregate-asphalt System

An asphalt mixture is a multi-level and multi-phase granular material, in which the complicated aggregate characteristics, interface effect, and migration behaviors determine the segregation properties, compaction quality, and mechanical responses. Elucidating the mesoscopic mechanism of asphalt mixtures and providing a theoretical basis for the design optimization, construction control, and performance analysis of asphalt mixtures helps improve the durability of asphalt pavement. This paper reviews the outcomes of existing research on aggregate-asphalt systems. Asphalt mixtures used in paving, compaction, and service processes are regarded as different states of aggregate-asphalt systems with different degrees of freedom of migration. First, focusing on the aggregate characteristics, the effects of geometric morphologies and size of the aggregates on the performance of the asphalt mixture are analyzed; based on this analysis, the method for the calculation of composite geometric characteristics is described. Subsequently, considering the loose aggregate-asphalt system, the mesoscopic properties are described, including the contact-friction properties of the particle system and the interface interaction of the aggregate-asphalt system. Subsequently, the evaluation methods used for the segregation of asphalt mixture are summarized; the effect of particle migration on the segregation tendency of asphalt mixture is analyzed, and the forming mechanism of mixture segregation is discussed. Considering the compaction process of asphalt mixtures, the dynamic compaction properties of asphalt mixtures and the migration behaviors of particles are discussed; the influence of the geometric characteristics and the interface effect on the particle migration are analyzed, and the compaction process of the asphalt mixture is discussed based on the migration behaviors. Considering the compacted asphalt mixture, the spatial migration behavior of the aggregate-asphalt system is summarized, and the influence of the micromigration behavior on the mechanical strength properties of the asphalt mixture at the mesoscopic level is analyzed. Finally, the asphalt mixtures used in the transportation and paving, compaction, and service processes are defined as aggregate-asphalt systems with large-degree-of-freedom, small-degree-of-freedom, and micro-degree-of-freedom migration properties, respectively. The development tendency of interface behaviors and the migration dynamic properties of aggregate-asphalt systems are summarized, and prospects for further research are discussed. This review provides a reference for the basic theoretical research on the microscopic and mesoscopic characterization and mechanical response of asphalt mixtures, which will help improve mixture design, construction techniques, and maintenance quality.