回收青混合物和固体废物固化材料对冷再生青混合物的性能的影响
Benan Shu1,2, Guodong Zeng2, Yunlong Ma3
1National Engineering Research Center of Highway Maintenance Technology, Changsha University of Science & Technology, Changsha 410114, China.
Materials (Basel, Switzerland)
|October 26, 2024
概括
这项研究利用废物复原剂和固化材料 (SSM) 再生了老化的青混合物. 结果显示性能提高,特别是100%的SSM替代,提高了强度和稳定性.
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.
- 可持续建筑 可持续建筑
背景情况:
- 青混合物的老化给环境和经济带来了挑战.
- 用废物材料回收老青提供了一个可持续的解决方案.
- 固体废物固化材料 (SSM) 是传统水泥的替代品.
研究的目的:
- 评估再生青混合物 (RAM) 的性能,使用基于废物的复原剂和SSM.
- 评估再生青路面 (RAP) 和SSM替代水平对RAM属性的影响.
- 调查RAM性能增强背后的微结构机制.
主要方法:
- 使用废物复原剂再生老化的青混合物.
- 使用基于固体废物的固化材料 (SSM) 凝固混合物.
- 通过分割拉伸强度,轮跟踪和三点曲测试来评估RAM属性.
主要成果:
- 高达30%的RAP替代维持或增强了青混合物的性能.
- 100%的RAP替代导致分裂拉伸强度,动态稳定性和分裂强度比率下降.
- 100%的SSM替代显著增加了压力强度 (40%),动态稳定性 (32%),屈曲应变 (14%) 和裂变强度比率 (8%).
- SSM促进了水合酸和酸的形成,增加了固相体积,改善了孔隙填充.
结论:
- 基于废物的再生剂和SSM可以有效地再生老化的青混合物.
- 优化的SSM替代显著提高再生青混合物的机械性能.
- 由SSM引起的微结构变化有助于提高RAM的性能和耐用性.
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