通过建筑和拆除废弃物 (CDW) 回收来制定地质聚合物砂:一个全面的案例研究
Stefania Manzi1, Luca Baldazzi1, Andrea Saccani1
1Department of Civil, Chemical, Environmental and Materials Engineering, University of Bologna, Via Terracini 28, 40131 Bologna, Italy.
Materials (Basel, Switzerland)
|December 9, 2023
概括
带有循环混凝土聚合物的活性金属类砂由于附着的砂层而显示出较低的压力强度. 本研究探讨了它们作为可持续混凝土替代品的特性.
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.
- 环境科学 环境科学
背景情况:
- 建筑和拆除废物 (CDW) 在全球范围内不断增加,需要可持续的回收实践.
- 普通的波特兰水泥 (OPC) 生产有很高的二氧化碳排放,推动了对替代粘合剂的需求.
- 活性材料 (AAMs) 为OPC提供了一个有前途的环保替代品,特别是当与回收聚合物相结合时.
研究的目的:
- 调查在活性甲 (AAM) 砂中使用回收混凝土聚合物 (RCAs) 的可行性.
- 分析结合RCAs的新鲜和硬化AAM砂的性能.
- 识别挑战及其对AAM与RCAs绩效的影响.
主要方法:
- 为活性化金属类砂配制各种混合设计的配制,其中RCAs的百分比不同.
- 砂的新鲜性质 (例如可加工性) 和硬化性质 (例如压力强度,孔隙性) 的表征.
- 微结构分析,以了解粘附砂对RCAs的影响和活性化过程.
主要成果:
- 在RCAs上粘附的砂层增加了开放的孔隙性,并阻碍了甲甲的性激活.
- 压力强度随着RCA含量增加而下降:20MPa (12.5%RCA) 和15MPa (25%RCA) 在28天.
- 与使用天然聚合物的砂相比,强度的减少是显著的 (35%和50%).
结论:
- 虽然AAMs与RCAs显示出作为可持续材料的潜力,但附着的砂层构成了重大挑战.
- 需要进一步的研究,以减轻粘附砂对RCA性能的负面影响,以提高性能.
- 优化RCA处理或AAM配方对于开发可行的环保混凝土替代品至关重要.
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