质量GGBFS混凝土与循环聚合物混合为活性物质:可加工性,温度历史和强度
Yanlin Huo1,2,3, Jinguang Huang4, Xiaoyu Han1,2,3
1School of Civil Engineering, Harbin Institute of Technology, Harbin 150090, China.
Materials (Basel, Switzerland)
|August 26, 2023
概括
基于高炉渣 (HVGGBFS) 的高体积地面颗粒混凝土显示了大混凝土应用的潜力. 在减少水化热的同时,它需要仔细考虑可加工性和聚合物类型,以获得最佳性能.
科学领域:
- 土木工程 土木工程是指土木工程.
- 材料科学 材料科学 材料科学
背景情况:
- 大规模混凝土应用需要仔细管理热量产生.
- 地质颗粒高炉渣 (GGBFS) 提供了一种可持续的替代粘合剂,具有较低的水化热量.
- 回收聚合物为改善混凝土性能和可持续性提供了机会.
研究的目的:
- 为了评估使用基于高炉渣 (HVGGBFS) 的混凝土作为质混凝土的可行性.
- 调查GGBFS和回收聚合物的对混凝土可加工性,温度和强度的影响.
- 为了比较HVGGBFS混凝土与天然聚合物的性能,与回收聚合物的性能相比.
主要方法:
- 对模拟混凝土质量 (800 mm × 800 mm × 800 mm) 的混凝土样本进行实验调查.
- 粘合剂成分:75%的GGBFS和25%的普通波特兰水泥 (OPC).
- 测试可加工性 (沉),温度老化和压力强度.
主要成果:
- 与普通波特兰水泥 (OPC) 混凝土相比,HVGGBFS混凝土显著减少了水化热.
- GGBFS和回收聚合物的组合导致水化热比普通混凝土高11.2%.
- 使用HVGGBFS混凝土的可加工性 (沉降) 降低了31.3%,使用回收聚合材料进一步降低.
- 在使用循环聚合物时,由于活性,压缩强度增加了33.7% (7天) 和16.3% (28天).
结论:
- 基于HVGGBFS的混凝土是大质量混凝土的可行选择,可提供降低的水化热量.
- 在HVGGBFS混凝土中使用回收聚合物会对加工能力产生负面影响,但会提高压力强度.
- 进一步的研究可能会优化混合设计,以提高可加工性,同时保持强度的好处.
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