厂拌热再生混合料中RAP分散特性多尺度研究

RAP分散程度影响着混合料实际级配和参与再生沥青量等，随着近年来工程中RAP掺量持续增大，深入把握RAP分散程度实际状况及其影响，对提升厂拌热再生沥青混合料设计效果具有重要影响。.本项目结合理论研究、数值计算和室内实验，开发涵盖集料优选、数字图像处理、评价指标设计的基于CT扫描的再生混合料中RAP分散程度评价方法，系统研究混合料中RAP分散特性，及分散程度对混合料细观结构和宏观性能的影响，提出再生沥青混合料离散元模型和汉堡车辙虚拟实验技术，结合虚拟试验和CT扫描揭示交通荷载作用下考虑RAP分散特性的混合料损伤机理，提出基于性能改善的厂拌热再生沥青混合料优化设计技术。.项目成果可有效改善厂拌热再生沥青混合料使用性能，深化再生混合料损伤机理认识，可进一步促进厂拌热再生技术，尤其是大RAP掺量时该技术的推广与应用。

Dispersion degree of RAP influences distinct actual aggregate gradation and recycled asphalt content of mixture. With the increasing of RAP content in engineering in recent years, it is very important to grasp the actual condition and influence of RAP dispersion degree in order to improve the design effect of hot central plant recycling mixture..Combined with theoretical research, numerical calculation and laboratory experiments, a new method for evaluating the dispersion of RAP in recycled mixture is developed based on CT scanning, which covers aggregate selection, digital image processing and evaluation index design. The dispersion characteristics of RAP in the mixture and the influence on the microstructure and macroscopic properties of mixture are studied systematically. The discrete element model of recycled asphalt mixture and the virtual experiment technology of Hamburg rut are proposed. The damage mechanism of mixture considering the dispersion characteristics of RAP under traffic load is revealed combined with virtual test and CT scanning. An optimal design technology of hot central plant recycling mixture based on performance improvement was proposed..The results of the project can effectively improve the performance of hot central plant recycling mixture, deepen the understanding of damage mechanism of recycled mixture, and further promote the promotion and application of this technology, especially when the content of RAP is large.