回收青路面材料的特征,用于热现场回收
Fangting Qu1, Zhiyu Yang1, Zhengnan Liu2
1National Engineering Research Center of Highway Maintenance Technology, Changsha University of Science & Technology, Changsha 410114, China.
Materials (Basel, Switzerland)
|March 13, 2025
概括
老青路面的热现场回收 (HIR) 需要考虑再生青路面 (RAP) 层内的粘合剂老化差异. 在HIR过程中加热和削显著改变RAP特性,影响路面性能.
科学领域:
- 材料科学 材料科学 材料科学
- 土木工程 土木工程是指土木工程.
- 铺路工程 铺路工程 铺路工程
背景情况:
- 目前用于再生青路面 (RAP) 的热现场回收 (HIR) 方法并没有根据不同RAP层的青粘合剂老化进行区分处理.
- 对于HIR工艺,特别是加热和研磨,如何影响RAP内的青粘合剂和聚合物特性,人们的理解有限.
研究的目的:
- 为了研究RAP层内的青粘合剂的老化梯度.
- 澄清HIR的加热和研磨工艺对青粘合剂和聚合物特性的影响.
- 为优化老旧路面的HIR混合设计和应用提供建议.
主要方法:
- 使用宏观测试 (曲线束转变计,动态剪切转变计) 和显微技术 (扫描电子显微镜,里叶变换红外光谱) 评估RAP青老化梯度.
- 通过常规性能测试 (动态剪切流体测量仪,曲束流体测量仪) 和选分析,对RAP材料的加热和削效应进行评估.
主要成果:
- 拉普青粘合剂表现出自然的老化梯度,表面层比下层更老.
- HIR加热过程导致RAP青的二次老化,透率降低25.3%,软化点增加7.4%,柔性降低36.4%.
- 削过程导致RAP中的分级失效,损坏了14.4%的粗块.
结论:
- 青粘合剂的老化程度因RAP的深度而异.
- HIR 工艺显著改变了 RAP 粘合剂和聚合物的特性,需要在混合物设计中进行调整.
- 对于严重老化的路面,建议对上层RAP层进行单独的磨削和处理,HIR混合物设计要考虑到加热和磨削的影响.
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