Experimental Study of Creep Acoustic Emission Characteristics of Coal Bodies around Boreholes under Different Moisture Contents
Water content is an important factor in the deformation-destruction process of coal bodies. To analyze the influence of water on the creep acoustic emission (AE) characteristics of coal rock surrounding a borehole, we conducted graded loading creep AE tests of single-hole specimens with different wa...
| Main Authors: | , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2021-05-01
|
| Series: | Energies |
| Subjects: | |
| Online Access: | https://www.mdpi.com/1996-1073/14/11/3103 |
| _version_ | 1797532633574408192 |
|---|---|
| author | Tianjun Zhang Zhiqiang Ling Mingkun Pang Yukai Meng |
| author_facet | Tianjun Zhang Zhiqiang Ling Mingkun Pang Yukai Meng |
| author_sort | Tianjun Zhang |
| collection | DOAJ |
| description | Water content is an important factor in the deformation-destruction process of coal bodies. To analyze the influence of water on the creep acoustic emission (AE) characteristics of coal rock surrounding a borehole, we conducted graded loading creep AE tests of single-hole specimens with different water contents (0%, 4%, 8% and water-saturation) under uniaxial loading. The findings include the following: the water content affects the creep mechanical properties of the coal body around a borehole. The creep transient strain and steady-state strain increased exponentially with rising water content; the saturated specimen showed the highest increase, reaching 44.5% and 28.6%, respectively. The specimen water content affected the cumulative ringing count (CRC) and the axial strain during creep. The axial strain increased with rising water content, the CRC increased linearly with rising axial strain. The higher the water content, the greater the CRC rise. At different stress levels, the CRC in the 4%, 8% and saturated water content specimens changed by 43%, 53% and 74%, respectively. The AE ringing rate showed a pattern of grow–decline–stabilize at each creep stage. The AEs decreased significantly with the rising water content and the creep curve lagged behind the AE data. This paper provides guidelines for gas extraction, borehole maintenance and AE detection. |
| first_indexed | 2024-03-10T11:02:02Z |
| format | Article |
| id | doaj.art-fcbb754edbce4b1f8586d5e55a79868d |
| institution | Directory Open Access Journal |
| issn | 1996-1073 |
| language | English |
| last_indexed | 2024-03-10T11:02:02Z |
| publishDate | 2021-05-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Energies |
| spelling | doaj.art-fcbb754edbce4b1f8586d5e55a79868d2023-11-21T21:27:59ZengMDPI AGEnergies1996-10732021-05-011411310310.3390/en14113103Experimental Study of Creep Acoustic Emission Characteristics of Coal Bodies around Boreholes under Different Moisture ContentsTianjun Zhang0Zhiqiang Ling1Mingkun Pang2Yukai Meng3College of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, ChinaCollege of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, ChinaCollege of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, ChinaCollege of Safety Science and Engineering, Xi’an University of Science and Technology, Xi’an 710054, ChinaWater content is an important factor in the deformation-destruction process of coal bodies. To analyze the influence of water on the creep acoustic emission (AE) characteristics of coal rock surrounding a borehole, we conducted graded loading creep AE tests of single-hole specimens with different water contents (0%, 4%, 8% and water-saturation) under uniaxial loading. The findings include the following: the water content affects the creep mechanical properties of the coal body around a borehole. The creep transient strain and steady-state strain increased exponentially with rising water content; the saturated specimen showed the highest increase, reaching 44.5% and 28.6%, respectively. The specimen water content affected the cumulative ringing count (CRC) and the axial strain during creep. The axial strain increased with rising water content, the CRC increased linearly with rising axial strain. The higher the water content, the greater the CRC rise. At different stress levels, the CRC in the 4%, 8% and saturated water content specimens changed by 43%, 53% and 74%, respectively. The AE ringing rate showed a pattern of grow–decline–stabilize at each creep stage. The AEs decreased significantly with the rising water content and the creep curve lagged behind the AE data. This paper provides guidelines for gas extraction, borehole maintenance and AE detection.https://www.mdpi.com/1996-1073/14/11/3103creep testporous coal bodywater contentcumulative ringing countenergy |
| spellingShingle | Tianjun Zhang Zhiqiang Ling Mingkun Pang Yukai Meng Experimental Study of Creep Acoustic Emission Characteristics of Coal Bodies around Boreholes under Different Moisture Contents Energies creep test porous coal body water content cumulative ringing count energy |
| title | Experimental Study of Creep Acoustic Emission Characteristics of Coal Bodies around Boreholes under Different Moisture Contents |
| title_full | Experimental Study of Creep Acoustic Emission Characteristics of Coal Bodies around Boreholes under Different Moisture Contents |
| title_fullStr | Experimental Study of Creep Acoustic Emission Characteristics of Coal Bodies around Boreholes under Different Moisture Contents |
| title_full_unstemmed | Experimental Study of Creep Acoustic Emission Characteristics of Coal Bodies around Boreholes under Different Moisture Contents |
| title_short | Experimental Study of Creep Acoustic Emission Characteristics of Coal Bodies around Boreholes under Different Moisture Contents |
| title_sort | experimental study of creep acoustic emission characteristics of coal bodies around boreholes under different moisture contents |
| topic | creep test porous coal body water content cumulative ringing count energy |
| url | https://www.mdpi.com/1996-1073/14/11/3103 |
| work_keys_str_mv | AT tianjunzhang experimentalstudyofcreepacousticemissioncharacteristicsofcoalbodiesaroundboreholesunderdifferentmoisturecontents AT zhiqiangling experimentalstudyofcreepacousticemissioncharacteristicsofcoalbodiesaroundboreholesunderdifferentmoisturecontents AT mingkunpang experimentalstudyofcreepacousticemissioncharacteristicsofcoalbodiesaroundboreholesunderdifferentmoisturecontents AT yukaimeng experimentalstudyofcreepacousticemissioncharacteristicsofcoalbodiesaroundboreholesunderdifferentmoisturecontents |