Analysis and numerical calculation of a coupled creep and strain-softening model for soft rock tunnels.
Proper mechanical model selection is critical in tunnel support design and stability analysis, especially to reflect the creep and strain-softening behavior of soft rock. We present a coupled nonlinear Burgers strain-softening (NBSS) model and numerical calculation method to investigate the coupled...
| Main Authors: | , , , , |
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| Format: | Article |
| Language: | English |
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Public Library of Science (PLoS)
2021-01-01
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| Series: | PLoS ONE |
| Online Access: | https://doi.org/10.1371/journal.pone.0256243 |
| _version_ | 1818362924052250624 |
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| author | Jianjun Zhang Baicong Yao Yunhe Ao Chunzhe Jin Chuang Sun |
| author_facet | Jianjun Zhang Baicong Yao Yunhe Ao Chunzhe Jin Chuang Sun |
| author_sort | Jianjun Zhang |
| collection | DOAJ |
| description | Proper mechanical model selection is critical in tunnel support design and stability analysis, especially to reflect the creep and strain-softening behavior of soft rock. We present a coupled nonlinear Burgers strain-softening (NBSS) model and numerical calculation method to investigate the coupled effects of creep and strain-softening of soft rock tunnels. The nonlinear elastic-viscous model is used to simulate the steady creep behavior of mudstone, and the nonlinear viscoplastic strain-softening model is used to simulate the accelerated creep behavior and post-peak strength attenuation behavior. The experimental results show that the viscoplastic parameters and post-peak softening parameters of mudstone are highly sensitive to confining pressure and exhibit nonlinear characteristics. The accelerated creep curve obtained by the numerical calculation is consistent with the experiments, which verifies the model reliability. We use the NBSS and nonlinear Burgers Mohr-Coulomb (NBMC) models to calculate the plastic zone distribution characteristics and deformation law. The distribution of the plastic zone calculated by the NBSS model is larger with more localized fractures. The NBSS model is useful for studying the evolution of stress and displacement fields of complex surrounding rock mass, which provides important theoretical guidelines for the support design and stability analysis of soft rock tunnel engineering. |
| first_indexed | 2024-12-13T21:40:18Z |
| format | Article |
| id | doaj.art-e92045ae59044cf9a2a5e7708d54d556 |
| institution | Directory Open Access Journal |
| issn | 1932-6203 |
| language | English |
| last_indexed | 2024-12-13T21:40:18Z |
| publishDate | 2021-01-01 |
| publisher | Public Library of Science (PLoS) |
| record_format | Article |
| series | PLoS ONE |
| spelling | doaj.art-e92045ae59044cf9a2a5e7708d54d5562022-12-21T23:30:34ZengPublic Library of Science (PLoS)PLoS ONE1932-62032021-01-01168e025624310.1371/journal.pone.0256243Analysis and numerical calculation of a coupled creep and strain-softening model for soft rock tunnels.Jianjun ZhangBaicong YaoYunhe AoChunzhe JinChuang SunProper mechanical model selection is critical in tunnel support design and stability analysis, especially to reflect the creep and strain-softening behavior of soft rock. We present a coupled nonlinear Burgers strain-softening (NBSS) model and numerical calculation method to investigate the coupled effects of creep and strain-softening of soft rock tunnels. The nonlinear elastic-viscous model is used to simulate the steady creep behavior of mudstone, and the nonlinear viscoplastic strain-softening model is used to simulate the accelerated creep behavior and post-peak strength attenuation behavior. The experimental results show that the viscoplastic parameters and post-peak softening parameters of mudstone are highly sensitive to confining pressure and exhibit nonlinear characteristics. The accelerated creep curve obtained by the numerical calculation is consistent with the experiments, which verifies the model reliability. We use the NBSS and nonlinear Burgers Mohr-Coulomb (NBMC) models to calculate the plastic zone distribution characteristics and deformation law. The distribution of the plastic zone calculated by the NBSS model is larger with more localized fractures. The NBSS model is useful for studying the evolution of stress and displacement fields of complex surrounding rock mass, which provides important theoretical guidelines for the support design and stability analysis of soft rock tunnel engineering.https://doi.org/10.1371/journal.pone.0256243 |
| spellingShingle | Jianjun Zhang Baicong Yao Yunhe Ao Chunzhe Jin Chuang Sun Analysis and numerical calculation of a coupled creep and strain-softening model for soft rock tunnels. PLoS ONE |
| title | Analysis and numerical calculation of a coupled creep and strain-softening model for soft rock tunnels. |
| title_full | Analysis and numerical calculation of a coupled creep and strain-softening model for soft rock tunnels. |
| title_fullStr | Analysis and numerical calculation of a coupled creep and strain-softening model for soft rock tunnels. |
| title_full_unstemmed | Analysis and numerical calculation of a coupled creep and strain-softening model for soft rock tunnels. |
| title_short | Analysis and numerical calculation of a coupled creep and strain-softening model for soft rock tunnels. |
| title_sort | analysis and numerical calculation of a coupled creep and strain softening model for soft rock tunnels |
| url | https://doi.org/10.1371/journal.pone.0256243 |
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