机械和干燥收缩性能研究不同固化条件下从渣制成的超高性能混凝土
Jinxin Wang1, Jun Li1, Yan Gao2
1State Key Laboratory of Environment-Friendly Energy Materials, School of Materials and Chemistry, Southwest University of Science and Technology, Mianyang 621010, China.
Materials (Basel, Switzerland)
|September 14, 2024
概括
蒸汽固化显著提高了超高性能混凝土 (UHPC) 的强度,并减少了收缩. 与石英砂相比,渣作为聚合物进一步增强了机械性能,并优化了孔隙结构.
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:
- 超高性能混凝土 (UHPC) 提供卓越的机械性能,但需要优化固化和聚合物选择.
- 了解固化模式和替代聚合物的影响对于提高超高压电池性能和可持续性至关重要.
研究的目的:
- 调查蒸汽固化与标准固化的对UHPC的影响.
- 评估渣和石英砂作为聚合物的对UHPC强度和收缩的影响.
- 分析影响UHPC属性的微结构变化.
主要方法:
- 使用低热酸盐水泥制备UHPC.
- 标准固化和蒸汽固化方案的应用.
- 机械测试 (压力强度) 和干燥收缩测量.
- 使用X射线衍射 (XRD),热重力测量分析 (TG) 和侵入孔径测量 (MIP) 的微结构分析.
主要成果:
- 蒸汽固化显著增强了UHPC的机械属性,并减少了干燥收缩.
- 蒸汽固化2天的UHPC显示压力强度比28天标准固化高9.15%.
- 在标准固化下,渣聚合物的压力强度在28天内比标准沙子高12.64%.
- 蒸汽固化降低了Ca(OH) 2含量和优化了孔隙结构;渣进一步改善了机械性能和孔隙结构.
结论:
- 蒸汽固化是提高UHPC机械性能和耐久性的有效方法.
- 渣是UHPC的高质量石英砂的优质聚合物,提供增强的强度,减少收缩和优化的微观结构.
- 渣为可持续的超高压电压应用提供了一个生态合理且具有成本效益的替代方案.
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