在干湿循环过程中,一项实验研究研究了由煤炭固体废物和纳米复合材料纤维制成的水泥糊填充的机械性能和微观结构
Haodong Wang1, Qiangqiang Cheng2, Nan Zhou1
1School of Mining Engineering, China University of Mining and Technology, Xuzhou 221000, China.
Materials (Basel, Switzerland)
|May 25, 2024
概括
干湿循环显著降低了水泥糊补充 (CPB) 的强度,特别是在较早的固化年龄. 较长的固化时间 (28天) 提高了CPB对干湿周期的抵抗力,保持了机械性能和微观结构.
科学领域:
- 材料科学 材料科学 材料科学
- 地质技术工程 地质技术工程
- 采矿工程 采矿工程 采矿工程
背景情况:
- 混凝土糊补充 (CPB) 对于补充采矿的稳定性至关重要.
- 了解干湿周期等环境压力下的CPB行为对于结构完整性至关重要.
- 煤和飞灰是CPB配方中常见的废物材料.
研究的目的:
- 研究干湿周期对CPB的机械性能和微观结构的影响.
- 评估不同固化年龄对CPB对干湿条件的耐药性的影响.
- 为了提供对材料适合回填应用的见解.
主要方法:
- 使用煤炭,飞灰,水泥,玻璃纤维和纳米制备了CPB标本.
- 具有不同固化年龄 (7天和28天) 的标本经历了多次干湿周期.
- 测试了机械强度 (压力,拉力,剪切),并使用扫描电子显微镜 (SEM) 分析了微结构变化.
主要成果:
- 经过七个干湿周期后,CPB强度显著下降,特别是在7天治愈的标本中 (40-67%的减少).
- 经过28天的固化样本在七个干湿周期后只显示了轻微的强度减少.
- 在SEM分析中,发现孔隙性,裂和结构降解增加,干湿周期增加,特别是在年轻的标本中.
结论:
- 干湿循环严重损害了CPB的机械性能和微观结构.
- 固化时间为28天,增强了CPB对干湿条件的弹性.
- 这些发现为管理基于煤炭的固体废物和了解回填材料性能提供了有价值的数据.
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