关于导热高强度混凝土机械性能的实验研究
Xiaojun Li1, Shenglei Jia2, Longgang Chen3
1College of Safety Science and Engineering, Xi'an University of Science and Technology, Xi'an 710054, China.
Materials (Basel, Switzerland)
|February 13, 2025
概括
本研究探讨在超高性能混凝土 (UHPC) 中使用煤气化废渣 (CGS) 和碳化 (SiC). 研究发现,SiC增强了导热性和稳定性,UHPC在100%的SiC替代下达到182.2 MPa的压力强度.
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) 为基础设施提供了卓越的性能.
- 煤气化渣 (CGS) 是一种潜在的可持续聚合物,可以取代传统的沙子.
- 提高导热性对于桥梁和核设施等应用至关重要.
研究的目的:
- 研究使用CGS和碳化 (SiC) 在超高压制剂中的可行性.
- 分析CGS和SiC替代比率对UHPC特性的影响.
- 评估开发的UHPC的热性能和高温稳定性.
主要方法:
- 用不同比例的CGS和SiC替代石英砂来制备UHPC标本.
- 测试机械性能 (压力和裂变抗拉强度) 在7,14和28天.
- 评估热性能,包括在高温下 (110-500°C) 的质量损失率和压力强度.
- 使用工业计算机断层扫描 (ICT) 进行微结构分析.
主要成果:
- 使用CGS和SiC的UHPC达到159.5MPa的最大28天压力强度和15.30MPa的裂变强度.
- 加入SiC显著提高了导热率和热稳定性.
- 在高温处理后,压力强度增加,在100%的SiC替代下达到182.2 MPa.
- 混凝土爆破发生在300°C以上;较低强度的样本表现出更好的高温爆破阻力.
- ICT发现,较高的SiC比率导致较少的毛孔缺陷和较大的个体毛孔.
结论:
- CGS和SiC是生产高性能UHPC的可行,可持续的替代品.
- 加入SiC可以提高UHPC的热性能和耐高温性能.
- 微结构分析提供了对影响材料性能的孔隙结构的见解.
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