Acoustic Emission Multi-Parameter Analysis of Dry and Saturated Sandstone with Cracks under Uniaxial Compression

Hongru Li, Rongxi Shen, Dexing Li, Haishan Jia, Taixun Li, Tongqing Chen and Zhenhai Hou
Additional contact information
Hongru Li: School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
Rongxi Shen: School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
Dexing Li: School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
Haishan Jia: School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
Taixun Li: School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
Tongqing Chen: School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China
Zhenhai Hou: School of Safety Engineering, China University of Mining and Technology, Xuzhou 221116, Jiangsu, China

Energies, 2019, vol. 12, issue 10, 1-18

Abstract: In order to study the mechanics and acoustic emission (AE) characteristics of fractured rock under water-rock interaction, dried and saturated sandstone samples with prefabricated double parallel cracks were prepared. Then, uniaxial compression experiments were performed to obtain their AE signals and crack propagation images. The results show that water reduces the strength and fracture toughness of fractured sandstone and enhances plasticity. After saturation, the samples start to crack earlier; the cracks grow slowly; the failure mode is transformed from shear failure along the prefabricated cracks to combined shear and tensile failure; more secondary cracks are produced. The saturated samples release less elastic energy and weaker AE signals in the whole failure process. However, their AE precursor information is more obvious and advanced, and their AE sources are more widely distributed. Compared with dry specimens, the AE frequencies of saturated specimens in the early stage of loading are distributed in a lower frequency domain. Besides, the saturated samples release less complex AE signals which are dominated by small-scale signals with weaker multi-fractal characteristics. After discussion and analysis, it is pointed out that this may be because water makes rock prone to inter-granular fracture rather than trans-granular fracture. The water lubrication also may reduce the amplitude of middle-frequency band signals produced by the friction on the fracture surface. Multi-fractal parameters can provide more abundant precursory information for rock fracture. This is of great significance to the stability of water-bearing fractured rock mass and its monitoring, and is conducive to the safe exploitation of deep energy.

Keywords: water-rock interaction; prefabricated crack; failure mode; acoustic emission; multi-fractal (search for similar items in EconPapers)
JEL-codes: Q Q0 Q4 Q40 Q41 Q42 Q43 Q47 Q48 Q49 (search for similar items in EconPapers)
Date: 2019
References: View references in EconPapers View complete reference list from CitEc
Citations: View citations in EconPapers (1)

Downloads: (external link)
https://www.mdpi.com/1996-1073/12/10/1959/pdf (application/pdf)
https://www.mdpi.com/1996-1073/12/10/1959/ (text/html)

Related works:
This item may be available elsewhere in EconPapers: Search for items with the same title.

Export reference: BibTeX RIS (EndNote, ProCite, RefMan) HTML/Text

Persistent link: https://EconPapers.repec.org/RePEc:gam:jeners:v:12:y:2019:i:10:p:1959-:d:233274

Access Statistics for this article

Energies is currently edited by Ms. Agatha Cao

More articles in Energies from MDPI
Bibliographic data for series maintained by MDPI Indexing Manager ().