Analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3D geomechanical model tests
To investigate the formation of zonal disintegration phenomenon in deep rock mass under high axial geostress, 3D geomechanical model tests for two rock strengths are carried out via capacity of deep rock breakage mechanics and supporting technique model test. Considering the maximum principal stress...
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2019-06-01
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doaj-c2d58cc4b94a47b3aa072a10e607d2232020-11-24T22:08:08ZengJVE InternationalJournal of Vibroengineering1392-87162538-84602019-06-012141163117410.21595/jve.2019.2061920619Analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3D geomechanical model testsPu Yuan0Ying Xu1School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan, 232001, P. R. ChinaSchool of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan, 232001, P. R. ChinaTo investigate the formation of zonal disintegration phenomenon in deep rock mass under high axial geostress, 3D geomechanical model tests for two rock strengths are carried out via capacity of deep rock breakage mechanics and supporting technique model test. Considering the maximum principal stress along the tunnel axis, 3D geomechanical model tests are carried out in a loading procedure of first loading to initial geostress, then excavating the tunnel with blasting construction, and finally overloading the stress along the tunnel. Due to unloading effect, radial strain is tensile and tangential strain is compressive around excavated tunnel after excavation complete, which indicates a radial tension and circumferential compression stress state. With continuous overloading of axial stress, values of both radial tensile strain and tangential compressive strain increase, then ring fracture appears due to large radial tensile strain. After axial overloading, an interval distribution of peaks and troughs is shown in radial tensile strain distribution around excavated tunnel, which indicates a formation of zonal disintegration. By cutting the rectangular cemented sand model, a distinct zonal disintegration phenomenon emerges, and an apparent shrinkage of excavated tunnel is also shown due to radial deformation towards excavated tunnel. The larger the rock strength is, the less the tunnel shrinkage is, the smaller the radius of fracture zone. After statistical analyses of three ring tensile fracture zones, the radius scale factor of fracture zone in zonal disintegration is about 1.28.https://www.jvejournals.com/article/20619deep rock masszonal disintegration3D geomechanical model testhigh axial geostressaxial overloadingdeformation characteristics |
collection |
DOAJ |
language |
English |
format |
Article |
sources |
DOAJ |
author |
Pu Yuan Ying Xu |
spellingShingle |
Pu Yuan Ying Xu Analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3D geomechanical model tests Journal of Vibroengineering deep rock mass zonal disintegration 3D geomechanical model test high axial geostress axial overloading deformation characteristics |
author_facet |
Pu Yuan Ying Xu |
author_sort |
Pu Yuan |
title |
Analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3D geomechanical model tests |
title_short |
Analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3D geomechanical model tests |
title_full |
Analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3D geomechanical model tests |
title_fullStr |
Analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3D geomechanical model tests |
title_full_unstemmed |
Analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3D geomechanical model tests |
title_sort |
analyses on deformation and fracture evolution of zonal disintegration during axial overloading in 3d geomechanical model tests |
publisher |
JVE International |
series |
Journal of Vibroengineering |
issn |
1392-8716 2538-8460 |
publishDate |
2019-06-01 |
description |
To investigate the formation of zonal disintegration phenomenon in deep rock mass under high axial geostress, 3D geomechanical model tests for two rock strengths are carried out via capacity of deep rock breakage mechanics and supporting technique model test. Considering the maximum principal stress along the tunnel axis, 3D geomechanical model tests are carried out in a loading procedure of first loading to initial geostress, then excavating the tunnel with blasting construction, and finally overloading the stress along the tunnel. Due to unloading effect, radial strain is tensile and tangential strain is compressive around excavated tunnel after excavation complete, which indicates a radial tension and circumferential compression stress state. With continuous overloading of axial stress, values of both radial tensile strain and tangential compressive strain increase, then ring fracture appears due to large radial tensile strain. After axial overloading, an interval distribution of peaks and troughs is shown in radial tensile strain distribution around excavated tunnel, which indicates a formation of zonal disintegration. By cutting the rectangular cemented sand model, a distinct zonal disintegration phenomenon emerges, and an apparent shrinkage of excavated tunnel is also shown due to radial deformation towards excavated tunnel. The larger the rock strength is, the less the tunnel shrinkage is, the smaller the radius of fracture zone. After statistical analyses of three ring tensile fracture zones, the radius scale factor of fracture zone in zonal disintegration is about 1.28. |
topic |
deep rock mass zonal disintegration 3D geomechanical model test high axial geostress axial overloading deformation characteristics |
url |
https://www.jvejournals.com/article/20619 |
work_keys_str_mv |
AT puyuan analysesondeformationandfractureevolutionofzonaldisintegrationduringaxialoverloadingin3dgeomechanicalmodeltests AT yingxu analysesondeformationandfractureevolutionofzonaldisintegrationduringaxialoverloadingin3dgeomechanicalmodeltests |
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1725817527797284864 |