土作为结构混凝土中的混凝土添加剂:可加工性,机械性能,耐用性和可持续性性能
Bastian Strybny1, Tobias Schack1, Julian Link1
1Institute of Building Materials Science, Leibniz Unviversity Hannover, 30167 Hannover, Germany.
Materials (Basel, Switzerland)
|September 28, 2024
概括
烧焦粘土 (CCs) 通过减少二氧化碳排放来增强环保混凝土. 虽然影响了可加工性,但CC提高了28天的强度和耐用性,为普通波特兰水泥 (OPC) 提供了一个可持续的替代品.
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:
- 烧焦粘土 (CCs) 正在被探索作为补充性水泥材料 (SCMs),以降低混凝土中的含量和二氧化碳排放.
- 工业界对复合水泥中的CC感兴趣,但它们作为直接混凝土添加剂的应用有限.
研究的目的:
- 研究CCs对混凝土混凝土的新鲜和硬化性能的影响.
- 为了评估不同CC含量和超级可塑剂剂量的混凝土的性能.
主要方法:
- 测试了四种混凝土混合设计,具有三种超级可塑剂水平 (12种变化).
- 评估的属性包括可加工性,出血性,早期和28天强度,碳化耐药性,结解性和化物迁移.
主要成果:
- CCs影响了可加工性,可通过高超塑性剂使用来管理.
- 增加的CC含量减少了出血,并提高了28天的强度,达到30%的重量%,超过普通波特兰水泥 (OPC).
- 随着CC的增加,二氧化碳阻力下降,但可比率高达15%;结解和化物阻力有所改善.
结论:
- 混凝土混凝土为可持续混凝土生产提供了可行的途径,提高了耐用性,减少了对环境的影响.
- 性能优势,包括增强强度和耐久性,支持CC作为混凝土添加剂的更广泛采用.
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