Energy evolution and failure characteristics of single fissure carbonaceous shale under drying−wetting cycles
In order to investigate the energy evolution and failure characteristics of carbonaceous shale containing single fissure under drying−wetting cycles, the intact carbonaceous shale samples and the carbonaceous shale samples with fissure angles of 30°, 45° and 60° were prepared. MTS815 rock mechanics...
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| Format: | Article |
| Language: | English |
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SCIENCE PRESS , 16 DONGHUANGCHENGGEN NORTH ST, BEIJING, PEOPLES R CHINA, 100717
2022-07-01
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| Series: | Rock and Soil Mechanics |
| Subjects: | |
| Online Access: | http://rocksoilmech.whrsm.ac.cn/EN/10.16285/j.rsm.2021.6657 |
| _version_ | 1828373638256001024 |
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| author | LIU Xin-xi LI Yu FAN Zi-jian LI Sheng-nan WANG Wei-wei DONG Peng |
| author_facet | LIU Xin-xi LI Yu FAN Zi-jian LI Sheng-nan WANG Wei-wei DONG Peng |
| author_sort | LIU Xin-xi |
| collection | DOAJ |
| description | In order to investigate the energy evolution and failure characteristics of carbonaceous shale containing single fissure under drying−wetting cycles, the intact carbonaceous shale samples and the carbonaceous shale samples with fissure angles of 30°, 45° and 60° were prepared. MTS815 rock mechanics test system was used to conduct triaxial compression tests under different drying−wetting cycles. The influence of drying−wetting cycles on the strength, failure mode and energy evolution of single fissure carbonaceous shale were studied. The results show that the elastic energy and dissipated energy at crack initiation stress, damage stress and peak stress present exponential relationships with drying-wetting cycles. The elastic energy and dissipated energy at crack initiation stress and dissipated energy at damage stress are less sensitive to drying−wetting cycle, while the sensitivities of elastic energy at damage stress, and elastic energy and dissipated energy at peak stress are relatively high. The failure mode of carbonaceous shale is dominated by drying−wetting cycle and fissure angle, in which the drying-wetting cycle is the main controlling factor, and the fissure angle is the secondary controlling factor. It is found that tensile shear failure occurs in dry rock sample with fissure angle of 30°, while the dry rock sample with fissure angle of 45°and 60° are subjected to shear failure. With the increase of the number of drying−wetting cycles, the macroscopic length of the main crack increases, the density of secondary cracks increases, and the failure mode transforms to shear-tension composite failure. With the increase of the number of drying−wetting cycles, the energy storage level at crack initiation stress Kci and the energy storage level at damage stress Kcd increase gradually. The higher the energy storage level at crack initiation and damage stress, the more likely the crack initiation and rock damage occur. Kcd can be used as a warning indicator of rock failure. A larger Kcd indicates that the rock is more vulnerable to failure. |
| first_indexed | 2024-04-14T07:21:41Z |
| format | Article |
| id | doaj.art-710830ed47eb401d903875e552f58745 |
| institution | Directory Open Access Journal |
| issn | 1000-7598 |
| language | English |
| last_indexed | 2024-04-14T07:21:41Z |
| publishDate | 2022-07-01 |
| publisher | SCIENCE PRESS , 16 DONGHUANGCHENGGEN NORTH ST, BEIJING, PEOPLES R CHINA, 100717 |
| record_format | Article |
| series | Rock and Soil Mechanics |
| spelling | doaj.art-710830ed47eb401d903875e552f587452022-12-22T02:06:09ZengSCIENCE PRESS , 16 DONGHUANGCHENGGEN NORTH ST, BEIJING, PEOPLES R CHINA, 100717Rock and Soil Mechanics1000-75982022-07-014371761177110.16285/j.rsm.2021.6657Energy evolution and failure characteristics of single fissure carbonaceous shale under drying−wetting cyclesLIU Xin-xi0 LI Yu1FAN Zi-jian2LI Sheng-nan3WANG Wei-wei4DONG Peng 51. School of Civil Engineering, Changsha University of Science and Technology, Changsha, Hunan 410114, China1. School of Civil Engineering, Changsha University of Science and Technology, Changsha, Hunan 410114, China1. School of Civil Engineering, Changsha University of Science and Technology, Changsha, Hunan 410114, China2. School of Architectural Engineering, Hunan Institute of Engineering, Xiangtan, Hunan 411101, China1. School of Civil Engineering, Changsha University of Science and Technology, Changsha, Hunan 410114, China1. School of Civil Engineering, Changsha University of Science and Technology, Changsha, Hunan 410114, China In order to investigate the energy evolution and failure characteristics of carbonaceous shale containing single fissure under drying−wetting cycles, the intact carbonaceous shale samples and the carbonaceous shale samples with fissure angles of 30°, 45° and 60° were prepared. MTS815 rock mechanics test system was used to conduct triaxial compression tests under different drying−wetting cycles. The influence of drying−wetting cycles on the strength, failure mode and energy evolution of single fissure carbonaceous shale were studied. The results show that the elastic energy and dissipated energy at crack initiation stress, damage stress and peak stress present exponential relationships with drying-wetting cycles. The elastic energy and dissipated energy at crack initiation stress and dissipated energy at damage stress are less sensitive to drying−wetting cycle, while the sensitivities of elastic energy at damage stress, and elastic energy and dissipated energy at peak stress are relatively high. The failure mode of carbonaceous shale is dominated by drying−wetting cycle and fissure angle, in which the drying-wetting cycle is the main controlling factor, and the fissure angle is the secondary controlling factor. It is found that tensile shear failure occurs in dry rock sample with fissure angle of 30°, while the dry rock sample with fissure angle of 45°and 60° are subjected to shear failure. With the increase of the number of drying−wetting cycles, the macroscopic length of the main crack increases, the density of secondary cracks increases, and the failure mode transforms to shear-tension composite failure. With the increase of the number of drying−wetting cycles, the energy storage level at crack initiation stress Kci and the energy storage level at damage stress Kcd increase gradually. The higher the energy storage level at crack initiation and damage stress, the more likely the crack initiation and rock damage occur. Kcd can be used as a warning indicator of rock failure. A larger Kcd indicates that the rock is more vulnerable to failure.http://rocksoilmech.whrsm.ac.cn/EN/10.16285/j.rsm.2021.6657triaxial compressionsingle fissure carbonaceous shaledrying?wetting cycleenergy evolutionfailure characteristics |
| spellingShingle | LIU Xin-xi LI Yu FAN Zi-jian LI Sheng-nan WANG Wei-wei DONG Peng Energy evolution and failure characteristics of single fissure carbonaceous shale under drying−wetting cycles Rock and Soil Mechanics triaxial compression single fissure carbonaceous shale drying?wetting cycle energy evolution failure characteristics |
| title | Energy evolution and failure characteristics of single fissure carbonaceous shale under drying−wetting cycles |
| title_full | Energy evolution and failure characteristics of single fissure carbonaceous shale under drying−wetting cycles |
| title_fullStr | Energy evolution and failure characteristics of single fissure carbonaceous shale under drying−wetting cycles |
| title_full_unstemmed | Energy evolution and failure characteristics of single fissure carbonaceous shale under drying−wetting cycles |
| title_short | Energy evolution and failure characteristics of single fissure carbonaceous shale under drying−wetting cycles |
| title_sort | energy evolution and failure characteristics of single fissure carbonaceous shale under drying wetting cycles |
| topic | triaxial compression single fissure carbonaceous shale drying?wetting cycle energy evolution failure characteristics |
| url | http://rocksoilmech.whrsm.ac.cn/EN/10.16285/j.rsm.2021.6657 |
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