自压缩混凝土的特性,用优化的泥和大米皮灰产生的自压缩混凝土,重点是质,流动性保留和耐用性
Abubakar Muhammad1, Karl-Christian Thienel1
1Institut für Werkstoffe des Bauwesens, Universität der Bundeswehr München, 85577 Neubiberg, Germany.
Materials (Basel, Switzerland)
|August 26, 2023
概括
在自压缩混凝土 (SCC) 中使用烧焦粘土 (CC) 和米灰 (RHA) 会影响其性能. CC和RHA的三元混合物比二元混合物更能提高SCC的性能,提高耐用性和可加工性.
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.
- 混凝土技术 混凝土技术
背景情况:
- 自压缩混凝土 (SCC) 需要密集的微观结构,以提高耐用性.
- 烧焦粘土 (CC) 和大米灰 (RHA) 是具有高水需求和特定表面积的补充性水泥材料 (SCM),对SCC应用构成挑战.
- 了解这些SCM对SCC属性的影响对于优化混凝土性能至关重要.
研究的目的:
- 研究用二元和三元混合CC和RHA替换部分水泥 (20体积%) 对SCC的流动性保留和耐用性的影响.
- 评估新鲜性质,质性行为和SCC的微观结构演变,其中包括CC和RHA.
- 通过快速化物迁移测试来评估SCC的耐用性.
主要方法:
- 使用实证方法考虑CC和RHA属性的SCC混合设计.
- 评估可变形性 (沉降流量,J环) 和粘度 (T500,V道).
- 监测流动性保留 (子方法),流动阻力 (风湿学测量),水合物相位演变 (热重力测量分析) 和耐久性 (快速化物迁移试验).
主要成果:
- 20电量%的CC替换对新鲜的SCC特性,流动性保留,压力强度或耐久性没有显著影响.
- 20电量%的RHA需要更高的超塑剂剂量,增加粘度,具有有限的流动性保留 (高达30分钟),以及更高的流阻,但通过消耗更多的氧化,提高了压力强度和抗性.
- 与二元RHA混合物相比,CC和RHA的三元混合物表现出优越的新鲜SCC特性,与二元CC混合物相比,提高了化物透阻力.
结论:
- 用20体积%的CC替换部分水泥对于SCC而言是可行的,而不会影响性能.
- 在SCC中包含20体积%的RHA需要在混合设计中进行调整,但提供了更好的强度和耐用性.
- CC和RHA的三元混合物提供了一种有希望的方法来优化SCC性能,平衡可加工性和耐用性.
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