红色砂岩破裂的裂演变和碎形特征基于声学排放参数
Shun Liu1, Xiaobin Yang2, Jianing Wu1
1College of Emergency Management and Safety Engineering, China University of Mining & Technology (Beijing), Beijing, 100083, China.
Scientific reports
|October 22, 2024
概括
了解岩石微裂变的演变是防止工程故障的关键. 这项研究揭示了裂角度如何影响红色砂岩的强度和故障模式,使用声学排放监测.
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
- 岩石机械学 岩石机械学
背景情况:
- 岩石的不稳定性和工程项目的失败需要了解压力下的内部微裂演变.
- 断裂岩石质量在地质技术应用中很常见,需要对其机械行为的详细分析.
研究的目的:
- 为了研究红色砂岩中受到单轴负荷的内部微裂纹模式和演变规则.
- 探索裂角度,声辐射特性和破碎岩石的机械特性之间的关系.
主要方法:
- 在破碎的红色砂岩样本上进行了单轴负荷和声辐射 (AE) 监测测试.
- 对AE参数 (RA和AF值) 的分析和碎形理论被用来描述裂模式.
- 使用AE环数的D/S统计分析来评估碎形尺寸.
主要成果:
- 红色砂岩的压力强度与裂角度呈现出"U"形关系.
- 在30°和45°破裂的砂岩中观察到与AE响声计数率相关的显著应力下降.
- 损坏的开始主要是由于拉力裂,随后是拉力和剪切裂的增加,表明断裂不稳定性.
- 碎形维度显示了一个下降-上升-下降的趋势,裂纹倾向增加,反映了裂纹复杂性的变化.
结论:
- 这项研究阐明了裂纹角度在红色砂岩的机械反应和故障机制中的关键作用.
- 声波发射和碎形分析为监测和理解岩石断裂过程提供了有效的工具.
- 这些发现有助于理论框架,以防止岩石工程应用中的不稳定性和故障.
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