结合冷解和硫酸盐攻击煤炭基水泥填充:孔隙演变和损害建模
Lihui Zhang1,2, Cunfei Wang1,2, Bing Liang1,3
1School of Mining Engineering, Liaoning Technical University, Fuxin, 123000, Liaoning, China.
Scientific reports
|October 31, 2025
概括
在结合的冷解和硫酸盐攻击下,水泥填充后的耐用性显著降低. 优化水泥含量有效地减轻了这种损害,改善了寒冷干旱的采矿环境中的材料弹性.
科学领域:
- 地质技术工程 地质技术工程
- 材料科学 材料科学 材料科学
- 环境科学 环境科学
背景情况:
- 混凝土填充材料对于寒冷干旱地区的采矿稳定性至关重要.
- 这些材料面临着结解和硫酸盐攻击的重大耐用性挑战.
- 了解退化机制对于基础设施的寿命至关重要.
研究的目的:
- 为了研究在结合冷解和硫酸盐攻击下,煤糊填充后的耐久性降解.
- 分析这些合条件对材料特性和孔隙结构的影响.
- 开发一个模型和设计方法,以提高回填耐用性.
主要方法:
- 制备煤炭粘膏填充样本的方法.
- 交替冷解 (50个周期) 和硫酸盐侵蚀 (50天) 的实验.
- 对质量损失,机械性能,动态弹性模量和孔隙结构演变的系统分析 (入孔隙测量).
- 开发一个孔隙力学合损伤模型.
主要成果:
- 结合条件导致指数质量损失 (8.57-10.18%) 和强度严重降低 (压缩: 73.2-98.6%,曲: 70.8-94.7%).
- 观察到明显的毛孔粗化:有害毛孔增加 (5-15%至22-26%),中位孔径扩大 (0.18微米至0.53微米).
- 一个孔隙力学模型 (R2=0.94) 量化了协同作用的损害效应.
- 高混凝土比率 (3:1) 组 (FS-P2) 显示有害毛孔减少 (15%) 和强度保留改善 (15.4-29.0%).
结论:
- 结冰解和硫酸盐攻击通过孔隙结构的改变协同降低了水泥填充的耐用性.
- 较高的凝固比率有效地抑制了孔隙扩张并提高了材料的耐用性.
- 该研究提供了一种基于孔隙值的设计方法,用于优化寒冷干旱的采矿地区的回填耐用性.
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