Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Eine Plattform für die Wissenschaft: Bauingenieurwesen, Architektur und Urbanistik
Effect of Artificial Ground Freezing on Deep Excavation for Shield Tunnel Restoration: Field Application and Numerical Simulation
https://orcid.org/http://orcid.org/0000-0003-1829-9496
https://orcid.org/http://orcid.org/0000-0002-2040-0808
https://orcid.org/http://orcid.org/0009-0008-3365-4779
https://orcid.org/http://orcid.org/0009-0003-9766-067X
https://orcid.org/http://orcid.org/0000-0002-2040-8850
Massive ground subsidence occurred during the construction of the cross passage of two main railway tunnels through a geologic formation bearing unexpectedly high gas pressure near the Nakdong River in South Korea. This subsidence caused structural damage to shield tunnel segments. To replace the damaged segments with box structures, a broad and deep excavation employing diaphragm walls was carried out, and artificial ground freezing was applied to connect the box structures with the intact tunnels outside the diaphragm walls. In this study, a three-dimensional thermo-mechanically coupled numerical analysis was conducted to assess the impact of artificial ground freezing on deep excavation. In order to reduce computational time, a one-way coupled approach was adopted in the numerical model, where the thermal analysis was initially performed considering the geometry and construction process, followed by mechanical analysis that incorporated changes in the ground properties based on the freezing temperature. The proposed numerical model was validated by comparing the results with the in situ measurements. Furthermore, the behavior of tunnel segments located outside the diaphragm walls was numerically investigated in relation to the freezing and thawing process. During the freezing process, the tunnel segments experienced heaving due to frost expansion of the ground, while they subsided during the thawing process.
Effect of Artificial Ground Freezing on Deep Excavation for Shield Tunnel Restoration: Field Application and Numerical Simulation
https://orcid.org/http://orcid.org/0000-0003-1829-9496
https://orcid.org/http://orcid.org/0000-0002-2040-0808
https://orcid.org/http://orcid.org/0009-0008-3365-4779
https://orcid.org/http://orcid.org/0009-0003-9766-067X
https://orcid.org/http://orcid.org/0000-0002-2040-8850
Massive ground subsidence occurred during the construction of the cross passage of two main railway tunnels through a geologic formation bearing unexpectedly high gas pressure near the Nakdong River in South Korea. This subsidence caused structural damage to shield tunnel segments. To replace the damaged segments with box structures, a broad and deep excavation employing diaphragm walls was carried out, and artificial ground freezing was applied to connect the box structures with the intact tunnels outside the diaphragm walls. In this study, a three-dimensional thermo-mechanically coupled numerical analysis was conducted to assess the impact of artificial ground freezing on deep excavation. In order to reduce computational time, a one-way coupled approach was adopted in the numerical model, where the thermal analysis was initially performed considering the geometry and construction process, followed by mechanical analysis that incorporated changes in the ground properties based on the freezing temperature. The proposed numerical model was validated by comparing the results with the in situ measurements. Furthermore, the behavior of tunnel segments located outside the diaphragm walls was numerically investigated in relation to the freezing and thawing process. During the freezing process, the tunnel segments experienced heaving due to frost expansion of the ground, while they subsided during the thawing process.
Effect of Artificial Ground Freezing on Deep Excavation for Shield Tunnel Restoration: Field Application and Numerical Simulation
https://orcid.org/http://orcid.org/0000-0003-1829-9496
https://orcid.org/http://orcid.org/0000-0002-2040-0808
https://orcid.org/http://orcid.org/0009-0008-3365-4779
https://orcid.org/http://orcid.org/0009-0003-9766-067X
https://orcid.org/http://orcid.org/0000-0002-2040-8850
Massive ground subsidence occurred during the construction of the cross passage of two main railway tunnels through a geologic formation bearing unexpectedly high gas pressure near the Nakdong River in South Korea. This subsidence caused structural damage to shield tunnel segments. To replace the damaged segments with box structures, a broad and deep excavation employing diaphragm walls was carried out, and artificial ground freezing was applied to connect the box structures with the intact tunnels outside the diaphragm walls. In this study, a three-dimensional thermo-mechanically coupled numerical analysis was conducted to assess the impact of artificial ground freezing on deep excavation. In order to reduce computational time, a one-way coupled approach was adopted in the numerical model, where the thermal analysis was initially performed considering the geometry and construction process, followed by mechanical analysis that incorporated changes in the ground properties based on the freezing temperature. The proposed numerical model was validated by comparing the results with the in situ measurements. Furthermore, the behavior of tunnel segments located outside the diaphragm walls was numerically investigated in relation to the freezing and thawing process. During the freezing process, the tunnel segments experienced heaving due to frost expansion of the ground, while they subsided during the thawing process.
Effect of Artificial Ground Freezing on Deep Excavation for Shield Tunnel Restoration: Field Application and Numerical Simulation
Lecture Notes in Civil Engineering
Wu, Wei (Herausgeber:in) / Leung, Chun Fai (Herausgeber:in) / Zhou, Yingxin (Herausgeber:in) / Li, Xiaozhao (Herausgeber:in) / Park, Sangyeong (Autor:in) / Son, Youngjin (Autor:in) / Park, Hyeontae (Autor:in) / Kim, Hojong (Autor:in) / Choi, Hangseok (Autor:in)
Conference of the Associated research Centers for the Urban Underground Space ; 2023 ; Boulevard, Singapore
10.07.2024
6 pages
Aufsatz/Kapitel (Buch)
Elektronische Ressource
Englisch
Numerical Simulation of Effect of Foundation Pit Excavation on Underlain Shield Tunnel
| British Library Conference Proceedings | 2014
Numerical Simulation of Effect of Foundation Pit Excavation on Underlain Shield Tunnel
| Trans Tech Publications | 2014
Construction of extension shield tunnel using ground freezing method
| British Library Conference Proceedings | 1994