重复使用3D打印混凝土 (3DPC) 精细回收聚合物的潜力,作为减少3DPC中的水泥含量战略
Szymon Skibicki1, Karol Federowicz1, Marcin Hoffmann2
1Faculty of Civil and Environmental Engineering, West Pomeranian University of Technology in Szczecin, 70-310 Szczecin, Poland.
Materials (Basel, Switzerland)
|June 19, 2024
概括
来自废弃3D打印混凝土的精细回收聚合物可以在新的3D打印混凝土中取代高达50%的水泥,提高可持续性. 高达20%的更换率对物业的影响最小,提供了可行的环保建筑战略.
科学领域:
- 材料科学 材料科学 材料科学
- 可持续建筑 可持续建筑
- 添加剂制造 添加剂制造 添加剂制造
背景情况:
- 由于3D打印混凝土 (3DPC) 的建筑垃圾越来越多,因此需要可持续的管理策略.
- 水泥生产对环境有重大影响,推动了对替代粘合剂的研究.
- 回收材料为建筑中的循环经济方法提供了潜力.
研究的目的:
- 调查使用废3DPC中的精细回收聚合物 (fRA) 作为新3DPC混合物中的部分水泥替代品的可行性.
- 评估fRA结合对3DPC新鲜,硬化,可打印和可建造性质的影响.
- 通过生命周期评估 (LCA) 评估使用fRA的经济和环境效益.
主要方法:
- 准备好的3DPC混合物与fRA替代水泥在10,20,30,40和50体积%时混合.
- 进行了学测试,动态弹性模量测量,机械强度测试 (柔性和压力) 和开放的孔隙性分析.
- 执行打印测试,经济分析和环境LCA,以评估性能和可持续性.
主要成果:
- 技术上可以用fRA取代高达50%的水泥,但更高的比率 (超过20%) 会对打印能力,绿色强度和机械性能产生负面影响.
- 在不损害基本材料特性或显著改变混合物设计的情况下,可以达到高达20%体积的替换率.
- 通过增加fRA含量,LCA显著降低了成本 (高达24%) 和减少了二氧化碳排放 (高达48%) .
结论:
- 来自废弃3DPC的精细回收聚合物显示出作为增材制造中的可持续水泥替代品的巨大潜力.
- 对于超过20%体积的更换率,需要优化混合物设计,以减轻性能缺陷.
- 将fRA纳入高达20%的容量提供了一种实际方法,可以在不牺牲性能的情况下提高3D打印混凝土的可持续性.
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