乳化沥青与泡沫沥青冷再生技术发展综述

针对乳化沥青与泡沫沥青冷再生技术发展过程中的关键问题，介绍了冷再生技术的发展现状，分析了乳化沥青与泡沫沥青混合料的材料组分性能，总结了冷再生沥青混合料配合比设计方法和路面结构设计方法，论述了相关路用性能演化规律以及施工工艺和施工设备，提出了冷再生技术的未来发展趋势。研究结果表明：冷再生沥青混合料的材料组成成分间相互作用机制及强度破坏机理复杂，回收沥青混合料来源和掺量以及沥青老化程度、沥青以及外加剂种类及含量均会显著影响冷再生沥青混合料的材料性能；不同的冷再生沥青混合料设计方法在级配选择、沥青等级、成形方法、养护方式以及性能评价指标等方面差别较大，大多采用试验测试法指导配合比设计；冷再生沥青路面设计方法经历了从经验法到力学-经验法的转变，通常将冷再生材料视为无黏结颗粒材料或者沥青黏结材料进行结构设计，目前仍缺乏符合冷再生沥青混合料材料特性的力学失效设计准则；在工程应用方面，应充分考虑冷再生结构层位及力学响应，明确抗车辙、抗水损害、抗疲劳和低温抗开裂的性能需求，以指导冷再生沥青混合料的材料组成设计；未来应从施工工艺和材料组成两方面加强冷再生沥青混合料性能优化研究，建立以力学指标为基础的养生时间评估体系，完善适用于中国气候条件的冷再生结构层施工规范，加强现场试验的数据检测和收集工作，实现对冷再生沥青路面结构设计方程的有效标定。

Review on cold recycling technology development of emulsified asphalt and foamed asphalt

For the key research issues in the development of cold recycling technology of emulsified asphalt and foamed asphalt, the development status of cold recycling technology was introduced. The properties of material components of emulsified asphalt and foamed asphalt mixture were analyzed. The design methods of mix ratio of cold-recycled asphalt mixture and pavement structure were summarized. The evolution law of related road performance and construction technologies and equipment were discussed. The development trend of cold recycling technology in the future was proposed. Research results show that the interaction and strength failure mechanisms between material components of cold-recycled asphalt mixture are complicated. The material properties of cold-recycled asphalt mixture can be significantly affected by the source and content of recycled asphalt pavement, the aging degree of asphalt, and the type and content of asphalt and admixture. Different design methods of cold-recycled asphalt mixture are greatly different in terms of gradation selection, asphalt grade, forming method, maintenance method, and performance evaluation indexes. Most of them employ the experimental test method to guide the design of the mix ratio. The design method of cold-recycled asphalt pavement has experienced a transformation from an empirical method to a mechanical-empirical one. It usually regards the cold-recycled materials as unbonded granular materials or asphalt bonding materials for the structural design. At present, the mechanical failure design principles conforming to the material properties of cold-recycled asphalt mixture are still lacking. As for the engineering application, the cold-recycled structure layer and its mechanical response should be fully considered. The performance requirements of resistance to rutting, water damage, fatigue, and low temperature cracking should be identified to guide the design of material composition of cold-recycled asphalt mixture. In the future, the research on the performance optimization of cold-recycled asphalt mixture should be strengthened from the two aspects of construction technology and material composition. The maintenance time evaluation system based on the mechanical index needs to be established. Meanwhile, the construction specifications of cold-recycled structure layers suitable for China's climatic conditions should be further improved. Moreover, the data detection and collection of field test roads need to be strengthed to achieve the effective calibration of the structure design equation of cold-recycled asphalt pavement.