在热固化下,LHEC的强度和扩张具有不同的石膏含量
Bingxin Jin1, Shuanglei Wu1, Shujing Fan2
1School of Materials Science and Engineering, Zhejiang University, Hangzhou 310027, China.
Materials (Basel, Switzerland)
|December 17, 2024
概括
在低热膨胀水泥 (LHEC) 中增加石膏含量可以提高强度和膨胀,特别是在更高的温度下. 这种环保材料在炎热,潮湿的条件下提供了更好的耐用性.
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.
- 环境科学 环境科学
背景情况:
- 低热膨胀水泥 (LHEC) 是普通波特兰水泥 (OPC) 的环保替代品,可以减少二氧化碳排放.
- 通过减轻OPC在炎热潮湿环境中的强度逆转,LHEC提供了更长的使用寿命.
研究的目的:
- 研究不同剂量的石膏 (8-20%) 在不同固化温度 (20°C,50°C,80°C) 下对LHEC强度和扩张的影响.
- 阐明影响低温热环境下LHEC性能的潜在机制.
主要方法:
- 在不同的石膏剂量和固化温度下对LHEC强度和膨胀进行实验研究.
- 使用X射线衍射 (XRD),热重力测量分析 (TGA),扫描电子显微镜 (SEM) 和孔隙测量进行微结构分析.
主要成果:
- 确定了强度的"关键石膏剂量",随温度和年龄而增加.
- 较高的温度对高石LHEC的强度产生了积极的影响,但对低石配方的影响不大.
- 增加的石膏含量提高了膨胀速度和稳定时间;较高的温度减少了稳定时间和最终膨胀.
结论:
- 优化石膏剂量对于提高LHEC强度和在高热环境中扩张至关重要.
- 高温和石膏的增加促进了渣渣的水化和矿的形成,改善了微观结构.
- 对石膏含量和固化温度的战略调整可以显著提高LHEC在具有挑战性的气候应用中的性能.
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