Long-Term Mechanical Response of Jinping Ultra-Deep Tunnels Considering Pore Pressure and Engineering Disturbances
As the world’s deepest hydraulic tunnels, the Jinping ultra-deep tunnels provide world-class conditions for research on deep rock mechanics under extreme conditions. This study analyzed the time-dependent behavior of different tunneling sections in the Jinping tunnels using the Nishihara creep model...
Saved in:
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
MDPI AG
2025-07-01
|
| Series: | Applied Sciences |
| Subjects: | |
| Online Access: | https://www.mdpi.com/2076-3417/15/15/8166 |
| Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
| _version_ | 1849406105582567424 |
|---|---|
| author | Ersheng Zha Mingbo Chi Jianjun Hu Yan Zhu Jun Guo Xinna Chen Zhixin Liu |
| author_facet | Ersheng Zha Mingbo Chi Jianjun Hu Yan Zhu Jun Guo Xinna Chen Zhixin Liu |
| author_sort | Ersheng Zha |
| collection | DOAJ |
| description | As the world’s deepest hydraulic tunnels, the Jinping ultra-deep tunnels provide world-class conditions for research on deep rock mechanics under extreme conditions. This study analyzed the time-dependent behavior of different tunneling sections in the Jinping tunnels using the Nishihara creep model implemented in Abaqus. Validated numerical simulations of representative cross-sections at 1400 m and 2400 m depths in the diversion tunnel reveal that long-term creep deformations (over a 20-year period) substantially exceed instantaneous excavation-induced displacements. The stress concentrations and strain magnitudes exhibit significant depth dependence. The maximum principal stress at a 2400 m depth reaches 1.71 times that at 1400 m, while the vertical strain increases 1.46-fold. Based on this, the long-term mechanical behavior of the surrounding rock during the expansion of the Jinping auxiliary tunnel was further calculated and predicted. It was found that the stress concentration at the top and bottom of the left sidewall increases from 135 MPa to 203 MPa after expansion, identifying these as critical areas requiring focused monitoring and early warnings. The total deformation of the rock mass increases by approximately 5 mm after expansion, with the cumulative deformation reaching 14 mm. Post-expansion deformation converges within 180 days, with creep deformation of 2.5 mm–3.5 mm observed in both sidewalls, accounts for 51.0% of the total deformation during expansion. The surrounding rock reaches overall stability three years after the completion of expansion. These findings establish quantitative relationships between the excavation depth, time-dependent deformation, and stress redistribution and support the stability design, risk management, and infrastructure for ultra-deep tunnels in a stress state at a 2400 m depth. These insights are critical to ensuring the long-term stability of ultra-deep tunnels and operational safety assessments. |
| format | Article |
| id | doaj-art-aed03198607b44d0bc4872ffed17901c |
| institution | Kabale University |
| issn | 2076-3417 |
| language | English |
| publishDate | 2025-07-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj-art-aed03198607b44d0bc4872ffed17901c2025-08-20T03:36:30ZengMDPI AGApplied Sciences2076-34172025-07-011515816610.3390/app15158166Long-Term Mechanical Response of Jinping Ultra-Deep Tunnels Considering Pore Pressure and Engineering DisturbancesErsheng Zha0Mingbo Chi1Jianjun Hu2Yan Zhu3Jun Guo4Xinna Chen5Zhixin Liu6China Academy of Safety Science and Technology, No. 32 Beiyuan Road, Beijing 100012, ChinaChina Academy of Safety Science and Technology, No. 32 Beiyuan Road, Beijing 100012, ChinaState Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering, Shenzhen University, Shenzhen 518060, ChinaChina Academy of Safety Science and Technology, No. 32 Beiyuan Road, Beijing 100012, ChinaSchool of Emergency Management and Safety Engineering, China University of Mining and Technology-Beijing, Beijing 100083, ChinaSchool of Emergency Management and Safety Engineering, China University of Mining and Technology-Beijing, Beijing 100083, ChinaSafety Science and Engineering College, Liaoning Technical University, Huludao 125105, ChinaAs the world’s deepest hydraulic tunnels, the Jinping ultra-deep tunnels provide world-class conditions for research on deep rock mechanics under extreme conditions. This study analyzed the time-dependent behavior of different tunneling sections in the Jinping tunnels using the Nishihara creep model implemented in Abaqus. Validated numerical simulations of representative cross-sections at 1400 m and 2400 m depths in the diversion tunnel reveal that long-term creep deformations (over a 20-year period) substantially exceed instantaneous excavation-induced displacements. The stress concentrations and strain magnitudes exhibit significant depth dependence. The maximum principal stress at a 2400 m depth reaches 1.71 times that at 1400 m, while the vertical strain increases 1.46-fold. Based on this, the long-term mechanical behavior of the surrounding rock during the expansion of the Jinping auxiliary tunnel was further calculated and predicted. It was found that the stress concentration at the top and bottom of the left sidewall increases from 135 MPa to 203 MPa after expansion, identifying these as critical areas requiring focused monitoring and early warnings. The total deformation of the rock mass increases by approximately 5 mm after expansion, with the cumulative deformation reaching 14 mm. Post-expansion deformation converges within 180 days, with creep deformation of 2.5 mm–3.5 mm observed in both sidewalls, accounts for 51.0% of the total deformation during expansion. The surrounding rock reaches overall stability three years after the completion of expansion. These findings establish quantitative relationships between the excavation depth, time-dependent deformation, and stress redistribution and support the stability design, risk management, and infrastructure for ultra-deep tunnels in a stress state at a 2400 m depth. These insights are critical to ensuring the long-term stability of ultra-deep tunnels and operational safety assessments.https://www.mdpi.com/2076-3417/15/15/8166long-term creep behaviornumerical implementexcavation-induced responsedifferent depthstability analysis |
| spellingShingle | Ersheng Zha Mingbo Chi Jianjun Hu Yan Zhu Jun Guo Xinna Chen Zhixin Liu Long-Term Mechanical Response of Jinping Ultra-Deep Tunnels Considering Pore Pressure and Engineering Disturbances Applied Sciences long-term creep behavior numerical implement excavation-induced response different depth stability analysis |
| title | Long-Term Mechanical Response of Jinping Ultra-Deep Tunnels Considering Pore Pressure and Engineering Disturbances |
| title_full | Long-Term Mechanical Response of Jinping Ultra-Deep Tunnels Considering Pore Pressure and Engineering Disturbances |
| title_fullStr | Long-Term Mechanical Response of Jinping Ultra-Deep Tunnels Considering Pore Pressure and Engineering Disturbances |
| title_full_unstemmed | Long-Term Mechanical Response of Jinping Ultra-Deep Tunnels Considering Pore Pressure and Engineering Disturbances |
| title_short | Long-Term Mechanical Response of Jinping Ultra-Deep Tunnels Considering Pore Pressure and Engineering Disturbances |
| title_sort | long term mechanical response of jinping ultra deep tunnels considering pore pressure and engineering disturbances |
| topic | long-term creep behavior numerical implement excavation-induced response different depth stability analysis |
| url | https://www.mdpi.com/2076-3417/15/15/8166 |
| work_keys_str_mv | AT ershengzha longtermmechanicalresponseofjinpingultradeeptunnelsconsideringporepressureandengineeringdisturbances AT mingbochi longtermmechanicalresponseofjinpingultradeeptunnelsconsideringporepressureandengineeringdisturbances AT jianjunhu longtermmechanicalresponseofjinpingultradeeptunnelsconsideringporepressureandengineeringdisturbances AT yanzhu longtermmechanicalresponseofjinpingultradeeptunnelsconsideringporepressureandengineeringdisturbances AT junguo longtermmechanicalresponseofjinpingultradeeptunnelsconsideringporepressureandengineeringdisturbances AT xinnachen longtermmechanicalresponseofjinpingultradeeptunnelsconsideringporepressureandengineeringdisturbances AT zhixinliu longtermmechanicalresponseofjinpingultradeeptunnelsconsideringporepressureandengineeringdisturbances |