水泥糊的膨胀和强度与基于CaO的膨胀剂之间的关系
Tengfei Hua1, Zhiwei Cao1, Shijun Zhang1
1Yunnan Science and Technology Research Institute of Highway, Kunming 650051, China.
Materials (Basel, Switzerland)
|January 8, 2025
概括
将基于CaO的膨胀剂 (CEA) 添加到水泥糊中,可以增加膨胀,但由于孔径增加和微裂纹,强度降低. 更高的CEA剂量和矿物质添加剂含量加剧了这种效应,显示了扩张率和压力强度之间的线性反向关系.
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.
- 建筑材料 建筑材料
背景情况:
- 混凝土材料容易收缩,需要扩张剂.
- 基于CaO的膨胀剂 (CEA) 用于抵消收缩和提高耐用性.
- 了解CEA诱导的扩张和材料强度之间的相互作用对于结构完整性至关重要.
研究的目的:
- 研究基于CaO的膨胀剂 (CEA) 剂量与水泥糊的膨胀率之间的关系.
- 分析CEA对水泥糊的压力强度,微观结构和水合性的影响.
- 阐明CEA改性水泥糊中膨胀率和压力强度之间的相互作用机制.
主要方法:
- 用不同剂量的基于CaO的膨胀剂 (CEA) 制备水泥糊样本.
- 测量膨胀率,压力强度,多孔性和水合度.
- 液化产品的微观结构分析和表征.
- 扩张速率和压力强度之间的相关性分析.
主要成果:
- 添加CEA增加了水泥糊的膨胀率,多孔性和水合度.
- 添加CEA降低了水泥的紧度和压力强度.
- 在膨胀率和压力强度之间观察到线性反向关系.
- 增加矿物质添加剂含量,在恒定的CEA剂量下,也增加了扩张率.
结论:
- 基于CaO的膨胀剂 (CEA) 增强了水泥糊的膨胀,但通过增加孔隙性和微裂纹,降低了压力强度.
- 对强度的负面影响随着CEA和矿物质添加剂含量增加而加剧.
- 膨胀率是预测CEA修改的水泥材料压力强度降低的关键指标.
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