混合统一性评估和成型方法的研究,用于粉碎,,青混合物
Wenhua Wang1,2, Yi Lu3, Lingdi Kong1,2
1Shandong Expressway Infrastructure Construction Co., Ltd., Jinan 250000, China.
Materials (Basel, Switzerland)
|November 27, 2025
概括
这项研究引入了一个新的模型来评估碎青混合物 (CRAM) 的统一性,发现二次紧缩显著提高了性能,并减少了弹性回收. 为了增强CRAM,确定了最佳的混合和压缩过程.
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.
- 可持续路面技术 可持续路面技术
背景情况:
- 碎青混合物 (CRAM) 提供可持续的好处,但由于非标准化的统一性评估和有问题的弹性回收,面临采用障碍.
- 现有的方法无法充分评估混合均性和控制CRAM的弹性特性,限制了它们的广泛工程应用.
研究的目的:
- 开发CRAM的性能评估系统,解决混合均性和弹性回收方面的局限性.
- 通过优化其生产和性能特征来促进CRAM的工程应用.
主要方法:
- 建立了碎分布面积时刻模型和面积距离变化系数,以量化CRAM混合均性.
- 进行了压缩和直角试验,以调查混合参数 (过程,时间,温度) 和压缩参数 (温度,时间,方法) 对CRAM的影响.
主要成果:
- 与单次压缩相比,二次压缩显著提高了CRAM的机械性能,并将弹性回收率降低了76%.
- 预先将与聚合物混合 (45%的改进) 或延长混合时间 (18%的改进) 提高了混合均性.
- 最佳的混合和压缩温度 (180°C和170°C) 最大化了散装密度和马歇尔稳定性.
结论:
- 开发的模型和确定的最佳流程为改善CRAM统一性和性能提供了途径.
- 在CRAM中,二次压缩对于优越的机械性能和减少弹性回收至关重要.
- 建议对CRAM进行优化混合 (180°C,40s预混合+80s主要混合) 和二次压缩 (170°C/47次+80°C/23次).
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