Evaluation of fracture process by simultaneous measurement of acoustic and electromagnetic emission

通过同时测量声和电磁发射评估断裂过程

• 批准号: 15560082
• 负责人: MORI Yasuhiko
• 金额: $ 1.15万
• 依托单位: Nihon University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2003
• 资助国家: 日本
• 起止时间: 2003 至 2005
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-15560082/
• 关键词: electromagnetic emission; acoustic emission; rock; deformation; in-situ stress; Kaiser Effect; international exchange; Czech Republic; アコースティック・エミッション; 破壊; 強誘電体材料; AE; 雑音

Electromagnetic emission (EME), which is emanated when the fracture of the dielectric materials occurs, may be applicable for evaluating the fracture process occurred inside the materials, as one of the new method. In order to investigate the applicability of the new method, in this study, the simultaneous measurement of EME and AE (Acoustic Emission) was conducted on the deformation tests of rock samples, so that the relationship between the generation of EME and the occurrence of micro fractures, which is estimated by AE, would be confirmed. The following conclusions could be drawn from the present study:(1)EME generates only when the fresh surfaces due to cracking are created in the material.(2)A model for explaining the EME generation has been established based on the dipole moment of electric charges distributed on the crack surfaces and the vibration of crack walls.(3)Positive correlation between the signal amplitudes of EME and AE is found.(4)EME may be useful tools for studying the fracture process occurred inside the materials.(5)EME is very useful for estimating the rock in-situ stress, as a method in the field application.

当介电材料的断裂发生时，电磁发射（EME）可能适用于评估材料内部发生的断裂过程，这是一种新方法之一。为了研究新方法的适用性，在这项研究中，在岩石样品的变形测试中进行了EME和AE（声发射）的同时测量，因此EME的产生与微观发生之间的关系由AE估计的裂缝将得到确认。可以从本研究得出以下结论：（1）仅当在材料中创建裂纹引起的新鲜表面时，EME才会生成。（2）基于电的偶极力矩，建立了EME生成的模型（3）发现EME和AE信号幅度之间的正相关。（4）EME可能是研究材料内发生的裂缝过程的有用工具。（5）EME可能是有用的工具。（5）EME可能是有用的工具。（5） EME对于估计岩石原位应力非常有用，作为现场应用中的一种方法。

项目成果

Electromagnetic and acoustic emission fine spectra

电磁和声发射精细光谱

• 发表时间: 2006
• 期刊: Advanced Materials Research (Selected Papers : Proceedings of the 27th European Conference on Acoustic Emission Testing (in print)
• 作者: M.Nakagawa;H.Nakayasu;Josef Sikula
• 通讯作者: Josef Sikula

Y.Mori: "AB Kaiser effect and electromagnetic emission in the deformation of rock sample"Proceedings of the 26th European Conference on Acoustic Emission. (in print). (2004)

Y.Mori：“岩石样品变形中的AB凯撒效应和电磁发射”第26届欧洲声发射会议论文集。

T.Lokajicek: "Acoustic and electromagnetic emission from rocks"Proceedings of the EGU General Assembly. (in print). (2004)

T.Lokajicek：“岩石的声学和电磁发射”EGU 大会记录。

細木厚志: "繰返し変形下の岩石のAEと電磁放射"日本非破壊検査協会第14回AE総合コンファレンス論文集. 14. 147-150 (2003)

Atsushi Hosoki：“重复变形下岩石的 AE 和电磁辐射”日本无损检测学会第 14 届 AE 大会论文集 14. 147-150 (2003)。

AE KAISER EFFECT AND ELECTROMAGNETIC EMISSION IN THE DEFORMATION OF ROCK SAMPLE

• 发表时间: 2004
• 作者: Y. Mori;Y. Obata;J. Pavelka;J. Sikula;T. Lokajicek