用超吸收聚合物的水泥糊的压力强度和空隙分析的调查
1Department of Civil Engineering, Daegu University, Gyeongsan 38453, Republic of Korea.
Polymers
|July 27, 2024
概括
水泥糊中的超吸收聚合物 (SAP) 影响强度和空气空隙. 水固化增强了SAP的强度,而干燥的SAP导致比湿的SAP更细的空气空隙.
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:
- 超吸收性聚合物 (SAP) 越来越多地被用于修改水泥材料.
- 了解SAP对水泥糊性能的影响对于优化其使用至关重要.
- 水与水泥 (w/c) 比率和SAP形式 (干或湿) 是影响性能的关键变量.
研究的目的:
- 实验评估超吸收聚合物 (SAP) 剂量和形式对水泥糊压力强度和空气空隙特性的影响.
- 调查不同水与水泥 (w/c) 比率和固化条件对SAP修改的水泥糊的影响.
- 分析干燥与湿SAP整合对空气空隙参数 (如总空气含量,特定表面积和间距因子) 的影响.
主要方法:
- 准备的水泥糊的 w/c 比率为 0.4,0.5 和 0.6,SAP 剂量从 0.2% 到 0.5%.
- 在干燥和潮湿的形式中,SAP被纳入.
- 样品经过两种固化条件:20°C/60%RH (固化1) 和水固化 (固化2).
- 测量了压力强度,并使用28天固化后的图像分析进行空气空隙分析.
主要成果:
- 在Curing 1下,SAP的早期强度增加了,但后来强度下降了.
- 用水固化的SAP样本显示出更高的强度,特别是在较低的w/c比率 (0.4,0.5),但强度在w/c0.6.6下降.
- 与干燥的SAP相比,潮湿的SAP产生了更高的总空气含量和更粗的空气空隙结构 (更高的间距因子,更低的特定表面积).
结论:
- 在水泥糊中SAP的有效性高度依赖于水/水比和固化条件.
- 水固化通常有利于SAP修改的水泥糊的强度,除了高的w/c比率.
- SAP的形式显著影响空气空隙网络,由于粒子聚集,潮湿的SAP促进了更大,更间距的空气空隙.
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