高RAP掺量沥青混合料的预处理橡胶多尺度作用机制研究

废旧沥青混合料（RAP）与废旧轮胎的回收再利用，是实现我国道路建设绿色环保与节能减排的有效举措。而我国废旧沥青混合料与废旧轮胎的回收利用率不高，仍有关键技术难题需要突破。课题研究发现，通过合适的混合料设计，轮胎橡胶可显著提升含RAP沥青混合料的弹性性能及低温抗开裂性能。通过对橡胶进行预处理，可避免橡胶改性沥青混合料制备过程中，因橡胶溶胀作用对混合料性能带来的影响。因此提出通过使用与沥青成分类似的再生剂预处理橡胶，达到控制橡胶溶胀作用及提高沥青混合料中RAP掺量的目的。课题研究将首先探究再生剂处理橡胶的作用机理并优化制备工艺；接着通过多尺度试验及模拟，建立再生剂-橡胶-沥青不同成分间的作用机理；通过分析再生剂处理橡胶对混合料设计的影响，指导设计含高RAP掺量的沥青混合料。研究将为简化橡胶改性含RAP沥青混合料的应用提供指导，为推动提高废旧沥青混合料及废旧轮胎的回收再利用率提供理论基础。

The recycling and reusing of Reclaimed Asphalt Pavement (RAP) and waste tires is an effective strategy to fulfill green environmental protection, energy-saving, and emission reduction of the road construction. However, the recycling rate of waste asphalt mixture and waste tires is still low in China, and there are several critical technical problems that need to be solved. Based on previous research, crumb rubber could effectively improve the elastic property and low temperature cracking performance of asphalt mixture with RAP if appropriate mixture design was adopted. By pretreating crumb rubber, the influence of rubber swelling on the performance of asphalt mixture during the production of rubber modified asphalt mixture could be eliminated. Based on this, pretreating crumb rubber with rejuvenator, which had similar components as asphalt binder, will be proposed. With the implementation of the new technology, the swelling effect of crumb rubber could be controlled, and the RAP dosage in the asphalt mixture could be increased. The research study will firstly focus on the mechanism of treating crumb rubber with rejuvenator and preparation process optimization. Based on multi-scale tests and simulations, the interaction mechanism among different components of rejuvenator, crumb rubber, and asphalt binder will be established. The influence of treating crumb rubber with rejuvenator on mixture design will be analyzed, so as to guide the design of asphalt mixture with high content of RAP. The research could provide guidance on simplifying the application of rubber modification on the mixture with high RAP content. The study could lay basic in promoting the recycling percentage of RAP and waste tires.