The Deformation Law of a Soft-Rock Cavern by Step Excavation in a Pumped Storage Power Station
The surrounding rock stability of large underground caverns in a pumped storage power station is one of the most crucial problems in hydropower project design and construction. In the construction of hydropower projects in Southwest China, many underground soft-rock caverns in are excavated. Influen...
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MDPI AG
2023-08-01
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| Series: | Applied Sciences |
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| Online Access: | https://www.mdpi.com/2076-3417/13/15/8970 |
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| author | Ning Sun Xiaokai Li Shanggao Li Dake Hu Mengjiao Hu Faming Zhang Yiyan Zhong Menglong Dong Zinan Li |
| author_facet | Ning Sun Xiaokai Li Shanggao Li Dake Hu Mengjiao Hu Faming Zhang Yiyan Zhong Menglong Dong Zinan Li |
| author_sort | Ning Sun |
| collection | DOAJ |
| description | The surrounding rock stability of large underground caverns in a pumped storage power station is one of the most crucial problems in hydropower project design and construction. In the construction of hydropower projects in Southwest China, many underground soft-rock caverns in are excavated. Influenced by the high sidewall, high ground stress, large burial depth, and hydrodynamic pressure action, the deformation of the cavern is special, especially in terms of its soft-rock distribution. At present, most research of underground engineering on soft-rock stability focuses on small-scale tunnel excavations in homogeneous geological conditions, with limited studies on the large-scale excavation of deeply buried underground powerhouses in complex geological structures, featuring extensive soft-rock-layer exposure on the cavern wall. Therefore, it is particularly important to investigate the excavation method of and support measures for soft-rock caverns under complex geological conditions. Based on laboratory rock mechanics testing (petrographic analysis, uniaxial compressive strength tests, shear tests, and triaxial compression creep tests) and the distribution characteristics of the surrounding soft-rock layer of the proposed underground powerhouse, obtained from the survey, we discuss the excavation and support measurements. These include the influence of support measures on the deformation of the underground excavated cavern considering the inclination of rock layers, the impact of the excavation under supported conditions on the deformation of the underground cavern, and the correlation between the lining thickness and stress variation within the lining. |
| first_indexed | 2024-03-11T00:31:27Z |
| format | Article |
| id | doaj.art-856859ea79354d12b2df5618a4ef5c2c |
| institution | Directory Open Access Journal |
| issn | 2076-3417 |
| language | English |
| last_indexed | 2024-03-11T00:31:27Z |
| publishDate | 2023-08-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Applied Sciences |
| spelling | doaj.art-856859ea79354d12b2df5618a4ef5c2c2023-11-18T22:39:58ZengMDPI AGApplied Sciences2076-34172023-08-011315897010.3390/app13158970The Deformation Law of a Soft-Rock Cavern by Step Excavation in a Pumped Storage Power StationNing Sun0Xiaokai Li1Shanggao Li2Dake Hu3Mengjiao Hu4Faming Zhang5Yiyan Zhong6Menglong Dong7Zinan Li8Zhongnan Engineering Corporation Limited, Power China, Changsha 410014, ChinaSchool of Earth Science and Engineering, Hohai University, Nanjing 211100, ChinaZhongnan Engineering Corporation Limited, Power China, Changsha 410014, ChinaZhongnan Engineering Corporation Limited, Power China, Changsha 410014, ChinaZhongnan Engineering Corporation Limited, Power China, Changsha 410014, ChinaSchool of Earth Science and Engineering, Hohai University, Nanjing 211100, ChinaSchool of Earth Science and Engineering, Hohai University, Nanjing 211100, ChinaSchool of Earth Science and Engineering, Hohai University, Nanjing 211100, ChinaSchool of Earth Science and Engineering, Hohai University, Nanjing 211100, ChinaThe surrounding rock stability of large underground caverns in a pumped storage power station is one of the most crucial problems in hydropower project design and construction. In the construction of hydropower projects in Southwest China, many underground soft-rock caverns in are excavated. Influenced by the high sidewall, high ground stress, large burial depth, and hydrodynamic pressure action, the deformation of the cavern is special, especially in terms of its soft-rock distribution. At present, most research of underground engineering on soft-rock stability focuses on small-scale tunnel excavations in homogeneous geological conditions, with limited studies on the large-scale excavation of deeply buried underground powerhouses in complex geological structures, featuring extensive soft-rock-layer exposure on the cavern wall. Therefore, it is particularly important to investigate the excavation method of and support measures for soft-rock caverns under complex geological conditions. Based on laboratory rock mechanics testing (petrographic analysis, uniaxial compressive strength tests, shear tests, and triaxial compression creep tests) and the distribution characteristics of the surrounding soft-rock layer of the proposed underground powerhouse, obtained from the survey, we discuss the excavation and support measurements. These include the influence of support measures on the deformation of the underground excavated cavern considering the inclination of rock layers, the impact of the excavation under supported conditions on the deformation of the underground cavern, and the correlation between the lining thickness and stress variation within the lining.https://www.mdpi.com/2076-3417/13/15/8970pumped storage power stationsoft rockdeformation of surrounding rockBurgers–Mohr–Coulomb modeltriaxial compression creep testsupport measurements |
| spellingShingle | Ning Sun Xiaokai Li Shanggao Li Dake Hu Mengjiao Hu Faming Zhang Yiyan Zhong Menglong Dong Zinan Li The Deformation Law of a Soft-Rock Cavern by Step Excavation in a Pumped Storage Power Station Applied Sciences pumped storage power station soft rock deformation of surrounding rock Burgers–Mohr–Coulomb model triaxial compression creep test support measurements |
| title | The Deformation Law of a Soft-Rock Cavern by Step Excavation in a Pumped Storage Power Station |
| title_full | The Deformation Law of a Soft-Rock Cavern by Step Excavation in a Pumped Storage Power Station |
| title_fullStr | The Deformation Law of a Soft-Rock Cavern by Step Excavation in a Pumped Storage Power Station |
| title_full_unstemmed | The Deformation Law of a Soft-Rock Cavern by Step Excavation in a Pumped Storage Power Station |
| title_short | The Deformation Law of a Soft-Rock Cavern by Step Excavation in a Pumped Storage Power Station |
| title_sort | deformation law of a soft rock cavern by step excavation in a pumped storage power station |
| topic | pumped storage power station soft rock deformation of surrounding rock Burgers–Mohr–Coulomb model triaxial compression creep test support measurements |
| url | https://www.mdpi.com/2076-3417/13/15/8970 |
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