基于SEM的水泥填埋场中的宏观和微观特征及其关系的研究
Fengwen Zhao1, Jianhua Hu2, Taoying Liu1
1School of Resources and Safety Engineering, Central South University, Changsha 410083, China.
Materials (Basel, Switzerland)
|July 14, 2023
概括
扫描电子显微镜 (SEM) 图像分析量化了填充材料中的孔状特征. 孔隙复杂度增加,包括圆度和面积比,与材料强度降低相关.
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
- 图像分析 图像分析
背景情况:
- 扫描电子显微镜 (SEM) 提供微观结构可视化,但需要更深入的图像处理进行定量分析.
- 像核磁共振这样的传统方法可以提供多孔度数据,但缺乏详细的微观结构观测.
- 现有的SEM图像分析缺乏对材料性质相关的孔状特征的全面量化.
研究的目的:
- 开发一种定量方法,用于从填充材料的SEM图像中分析孔状特征.
- 为了研究在回填微观结构中的孔的碎形特征.
- 为了确定孔隙参数和回填的机械强度之间的关系.
主要方法:
- 使用Image-Pro Plus 6.0软件从SEM图像中提取孔隙参数 (面积,周长,比例,圆度).
- 应用了裂岛方法的碎形理论来确定孔隙的碎形特征.
- 构建了一个功能关系模型,以将毛孔参数与材料强度相关联.
主要成果:
- SEM图像分析显示,大多数回填孔是不规则的,表现出良好的碎形特征 (R2 > 0.96).
- 孔隙碎形尺寸与圆度,面积比和孔隙含量直接成比例,表明复杂性与形状和数量有关.
- 在材料强度和孔隙参数 (圆度,面积比,孔隙含量,碎形尺寸) 之间观察到线性反向关系.
结论:
- 孔隙特性显著影响回填材料的机械强度.
- 开发的SEM图像分析和分形方法提供了一种定量方法来评估孔隙复杂性.
- 了解孔隙结构-强度关系对于优化填充材料性能至关重要.
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