用AE技术在单次加载和多次加载下对贝山花岩损伤特征的实验研究
Zihui Wang1,2, Guanglei Zhou3,4, Xinbo Ge3,4
1State Key Laboratory of Mining Disaster Prevention and Control Cofounded By Shandong Province and the Ministry of Science and Technology, Shandong University of Science and Technology, Qingdao, 266590, Shandong, People's Republic of China. skd996340@sdust.edu.cn.
Scientific reports
|May 30, 2023
概括
了解宿主岩石损伤对于高水平放射性废物 (HLW) 处置至关重要. 声辐射 (AE) 分析揭示了在花岩中单重和多重负载条件下明显的损伤模式.
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
- 核废物管理 核废物管理
背景情况:
- 高水平放射性废物 (HLW) 的永久处置需要对宿主岩石行为的彻底了解.
- 花岩是一种常见的宿主岩石候选物,其在压力下损坏的特性对仓库安全至关重要.
- 声波发射 (AE) 是一种有价值的技术,可以实时监测岩石损伤的演变.
研究的目的:
- 在单重和多重负载条件下调查贝山花岩的损伤特性.
- 分析损坏的演变,使用声辐射 (AE) 监测.
- 为了将AE信号参数与不同的加载阶段和应力水平相关联.
主要方法:
- 在贝山花岩样本上进行单重和多重负荷测试.
- 采用声辐射 (AE) 监控系统来捕获损坏引起的信号.
- 分析了AE信号特征,包括主导频率,振幅和b值,与应力和负载历史相关.
主要成果:
- 单次负载显示在扩张后持续高的AE活动,随着峰值压力接近而下降.
- 多重加载在故障/残余阶段的弹性加载和卸载阶段产生了显著的AE信号.
- AE波形通常具有主导频率<200 kHz和振幅<80 dB;振幅与应力相关.
- AE b值表明微到宏裂纹比例和限制压力之间存在复杂的关系.
- 在多重负载场景中,AE a和b值证实了快速的微裂变发展和随后的宏裂变形成.
结论:
- 独特的AE信号模式区分了花岩中的单重和多重负载损伤演变.
- 在多重装载下卸载周期对AE活动有很大的贡献,突出了复杂的裂传播.
- AE参数,特别是b值,为HLW存储库设计提供了对微和宏裂发展的见解,这对HLW存储库设计至关重要.
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