在不同的水气相互作用下,关于砂泥石机械性能恶化的实验研究
Ning Jiang1,2, Dawei Yin1, Xia Jiang3
1State Key Laboratory of Mining Disaster Prevention and Control Co-founded by Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao, China.
Heliyon
|May 20, 2024
概括
水和气体显著削弱了沙泥石.
科学领域:
- 地质技术工程 地质技术工程
- 岩石机械学 岩石机械学
- 材料科学 是一种材料科学.
背景情况:
- 在复杂的环境条件下了解岩石质量的行为对于采矿安全至关重要.
- 水-岩石和气-岩石的相互作用可以显著改变岩石的特性.
- 砂泥石是地下矿山中常见的岩石类型,容易降解.
研究的目的:
- 为了研究水气合下沙泥石的拉伸性质的恶化机制.
- 量化不同浸泡条件 (粉碎气体,水粉碎气体,水) 对抗拉强度和故障模式的影响.
- 分析微观结构变化及其与宏观机械性质的相关性.
主要方法:
- 巴西的分裂试验是在沙泥石样本上进行的.
- 标本受到四种条件的影响:对比度 (CO),气浸泡 (MS),水气浸泡 (WM) 和水浸泡 (WS).
- 使用扫描电子显微镜 (SEM) 和3D全场应变测量 (XTDIC) 来分析微观结构和变形特征.
主要成果:
- 与对比组相比,所有浸泡条件都降低了单轴拉伸强度,而浸水 (WS) 显示了最显著的下降.
- 标本从脆性过渡到塑性故障,表现出更大的局部变形区域和更大的位移,特别是在WS组.
- 微观结构分析显示,浸泡样本的毛孔和毛孔面积增加,WS和MS组显示出最大的变化.
- 峰值前的储能能力下降,WS显示最大的减少,MS显示最小的减少.
- 水在沙性泥石上表现出比气体更强的腐蚀效应.
结论:
- 水气合显著降低了沙性泥石的拉伸性能.
- 恶化的程度取决于特定的流体 (水或气体) 和它们的组合.
- 这些发现对于评估高气体地下矿山中岩石质量的稳定性至关重要.
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