Study on Stress and Displacement of Axisymmetric Circular Loess Tunnel Surrounding Rock Based on Joint Strength
The development of an effective evaluation method suitable for loess-tunnel excavation is necessary to avoid the collapse accidents caused by tunnel excavation and any secondary disasters. Although the Fenner formulas and the modified Fenner formulas are widely used in tunnel engineering, a defect s...
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| Format: | Article |
| Language: | English |
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MDPI AG
2023-06-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/13/11/6836 |
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| author | Rongjin Li Weishi Bai Rongjian Li Jinshuo Jiang |
| author_facet | Rongjin Li Weishi Bai Rongjian Li Jinshuo Jiang |
| author_sort | Rongjin Li |
| collection | DOAJ |
| description | The development of an effective evaluation method suitable for loess-tunnel excavation is necessary to avoid the collapse accidents caused by tunnel excavation and any secondary disasters. Although the Fenner formulas and the modified Fenner formulas are widely used in tunnel engineering, a defect still exists in these formulas because the Mohr–Coulomb (M–C) criterion exaggerates the tensile strength of the surrounding rock of the loess tunnel. A newly modified Fenner formula was derived based on joint strength to overcome this deficiency. First, the expressions of stress and the radius of the plastic zone of the surrounding rock of the loess tunnel and the expressions of radial displacement were derived based on the stress-equilibrium equation of the axisymmetric plane and the joint strength. Then, the difference in the modified Fenner formulas based on the two kinds of strength criteria for the loess tunnel were compared. The results showed that the radius of the plastic zone and the radial displacement of the loess tunnel determined by the modified Fenner formula based on joint strength were larger than those determined by the modified Fenner formula based on M–C strength. However, the plastic stress of the plastic zone determined by the modified Fenner formula based on joint strength was smaller. The comparative analysis reveals that the modified Fenner formula based on joint strength can evaluate the stress and plastic-displacement field of the surrounding rock of a loess tunnel more reasonably. |
| first_indexed | 2024-03-11T03:10:31Z |
| format | Article |
| id | doaj.art-5af90b31b74549e08d1528490580f20a |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-11T03:10:31Z |
| publishDate | 2023-06-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-5af90b31b74549e08d1528490580f20a2023-11-18T07:37:21ZengMDPI AGApplied Sciences2076-34172023-06-011311683610.3390/app13116836Study on Stress and Displacement of Axisymmetric Circular Loess Tunnel Surrounding Rock Based on Joint StrengthRongjin Li0Weishi Bai1Rongjian Li2Jinshuo Jiang3School of Management, Xi’an University of Architecture & Technology, Xi’an 710055, ChinaInstitute of Geotechnical Engineering, Xi’an University of Technology, Xi’an 710048, ChinaInstitute of Geotechnical Engineering, Xi’an University of Technology, Xi’an 710048, ChinaInstitute of Geotechnical Engineering, Xi’an University of Technology, Xi’an 710048, ChinaThe development of an effective evaluation method suitable for loess-tunnel excavation is necessary to avoid the collapse accidents caused by tunnel excavation and any secondary disasters. Although the Fenner formulas and the modified Fenner formulas are widely used in tunnel engineering, a defect still exists in these formulas because the Mohr–Coulomb (M–C) criterion exaggerates the tensile strength of the surrounding rock of the loess tunnel. A newly modified Fenner formula was derived based on joint strength to overcome this deficiency. First, the expressions of stress and the radius of the plastic zone of the surrounding rock of the loess tunnel and the expressions of radial displacement were derived based on the stress-equilibrium equation of the axisymmetric plane and the joint strength. Then, the difference in the modified Fenner formulas based on the two kinds of strength criteria for the loess tunnel were compared. The results showed that the radius of the plastic zone and the radial displacement of the loess tunnel determined by the modified Fenner formula based on joint strength were larger than those determined by the modified Fenner formula based on M–C strength. However, the plastic stress of the plastic zone determined by the modified Fenner formula based on joint strength was smaller. The comparative analysis reveals that the modified Fenner formula based on joint strength can evaluate the stress and plastic-displacement field of the surrounding rock of a loess tunnel more reasonably.https://www.mdpi.com/2076-3417/13/11/6836loess tunnelmodified Fenner formulajoint strengthstressradius of plastic zone |
| spellingShingle | Rongjin Li Weishi Bai Rongjian Li Jinshuo Jiang Study on Stress and Displacement of Axisymmetric Circular Loess Tunnel Surrounding Rock Based on Joint Strength Applied Sciences loess tunnel modified Fenner formula joint strength stress radius of plastic zone |
| title | Study on Stress and Displacement of Axisymmetric Circular Loess Tunnel Surrounding Rock Based on Joint Strength |
| title_full | Study on Stress and Displacement of Axisymmetric Circular Loess Tunnel Surrounding Rock Based on Joint Strength |
| title_fullStr | Study on Stress and Displacement of Axisymmetric Circular Loess Tunnel Surrounding Rock Based on Joint Strength |
| title_full_unstemmed | Study on Stress and Displacement of Axisymmetric Circular Loess Tunnel Surrounding Rock Based on Joint Strength |
| title_short | Study on Stress and Displacement of Axisymmetric Circular Loess Tunnel Surrounding Rock Based on Joint Strength |
| title_sort | study on stress and displacement of axisymmetric circular loess tunnel surrounding rock based on joint strength |
| topic | loess tunnel modified Fenner formula joint strength stress radius of plastic zone |
| url | https://www.mdpi.com/2076-3417/13/11/6836 |
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