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Research Paper

Numerical study on tunnel design for securing stability at connection between submerged floating tunnel and bored tunnel

수중터널 지반 접속부 안정성 확보를 위한 터널 설계에 대한 수치해석적 연구

Seok-Jun Kang1
,
Gye-Chun Cho2*
강 석준1
,
조 계춘2*
1Ph.D. Student, Dept. of Civil and Environmental Engineering, KAIST
2Professor, Dept. of Civil and Environmental Engineering, KAIST
1학생회원, 한국과학기술원 건설및환경공학과 박사과정
2정회원, 한국과학기술원 건설및환경공학과 교수
* Corresponding Author
31 January 2020. pp. 77-89
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Abstract

Submerged floating tunnel (SFT) is a type of tunnel that allows tunnel segments to float underwater by buoyancy, and is being actively studied in recent years. When the submerged floating tunnel is connected to the ground, the tunnel and the bored tunnel inside the ground must be connected. There is risk that the stress will be concentrated at the connection between the two tunnels due to the different constraints and behavior of the two tunnels. Therefore, special design and construction methods should be applied to ensure the stability around the connection. However, previous studies on the stability at the connection site have not been sufficiently carried out, so study on the basic stage of the stability at connection site are necessary. In this study, numerical analysis simulating the connection between submerged floating tunnel and the bored tunnel confirmed that the shear strain concentration occurred in the ground around the connection, and it was analyzed that the structural factors can be handled during construction to have effects on the stability of the ground around the connection. Numerical results show that the risks from disproportionate displacements in the two tunnels can be mitigated through the construction of grouting material and joint design. Although the results from this study are qualitative results, it is expected that it will contribute to the determination of structural factors and risk areas that should be considered in the design of connections between the submerged floating tunnel and bored tunnel in the future studies.

Keywords
Submerged floating tunnel
Stability at connection site
Grouting material
Joint design
3D numerical analysis

수중 부유식 터널은 터널 세그먼트가 부력에 의해 수중에 부유하도록 하는 터널의 한 유형으로, 최근 활발히 연구되고 있다. 수중터널이 지면에 연결되면 수중터널과 지반 내부의 지중터널이 연결되어야 하는데, 두 터널의 서로 다른 구속조건과 거동 특성에 의해 두 터널의 연결부위에 응력이 집중될 가능성이 매우 높다. 따라서 연결부 주변의 안정성을 보장하기 위해 특별한 설계 및 시공 방법을 적용해야 한다. 그러나 연결부 안정성에 대한 기존 연구가 충분히 수행되지 않아서 기본적인 단계의 연결부 안정성 검토에 대한 연구가 필요하다. 이 연구에서는 수중터널과 지중터널의 연결부를 수치해석을 통해 모사하여 연결부 주변 지반에서 전단 변형 집중이 발생하는 것을 확인하였고, 시공 시 처리할 수 있는 구조적 인자가 연결부 주변 지반의 안정성 확보에 어떠한 영향을 가지는지에 대해 분석하였다. 수치해석 결과는 두 종류의 터널이 가지는 변위의 불균형으로 인한 위험이 그라우팅 재료 및 조인트 자유도 구성을 통해 완화될 수 있음을 보였다. 이 연구에서 도출된 결과는 비록 수치해석을 통한 정성적인 결과이지만, 향후 연구에서 수중터널과 지중터널의 연결의 설계 시 주요하게 고려해야 하는 구조적 인자 및 위험 지역을 판단하는 것에 기여할 것이라 판단된다.

키워드
수중터널
지반 접속부 안정성
그라우팅 재료
조인트 설계
3차원 수치해석
References
1
Chen, J.Y., Sun, S.N., Wang, B.G. (2008). “Dynamic analysis for the tether of submerged floating tunnel”, Chinese Journal of Computational Mechanics, Vol. 25, No. 4, pp. 488-493.
2
Hong, Y., Ge, F. (2010). “Dynamic response and structural integrity of submerged floating tunnel due to hydrodynamic load and accidental load”, Procedia Engineering, Vol. 4, pp. 35-50.
10.1016/j.proeng.2010.08.006
3
Itasca, F. (2013). Fast lagrangian analysis of continua in 3 dimensions, Online Manual, pp. 175-180.
4
Jakobsen, B. (2010). “Design of the submerged floating tunnel operating under various conditions”, Procedia Engineering, Vol. 4, pp. 71-79.
10.1016/j.proeng.2010.08.009
5
Kunisu, H., Mizuno, S., Mizuno, Y., Saeki, H. (1994). “Study on submerged floating tunnel characteristics under the wave condition”, Proceedings of the Fourth International Offshore and Polar Engineering Conference, Vol. 94, Osaka, pp. 96.
6
Mazzolani, F.M., Faggiano, B., Martire, G. (2010). “Design aspects of the AB prototype in the Qiandao Lake”, Procedia Engineering, Vol. 4, pp. 21-33.
10.1016/j.proeng.2010.08.005
7
Nilsen, B., Palmstrøm, A. (2001). “Stability and water leakage of hard rock subsea tunnels”, Proceedings of the International Conference on Modern Tunneling Science and Technology, Kyoto, pp. 497-502.
10.1201/9780203746653-85
8
Oh, S.H., Park, W.S., Jang, S.C., Kim, D.H. (2013). “Investigation on the behavioral and hydrodynamic characteristics of submerged floating tunnel based on regular wave experiments”, Journal of the Korean Society of Civil Engineers, Vol. 33, No. 5, pp. 1887-1895.
10.12652/Ksce.2013.33.5.1887
9
Shi, P., Zhang, D., Pan, J., Liu, W. (2016). “Geological investigation and tunnel excavation aspects of the weakness zones of Xiang'an subsea tunnels in China”, Rock Mechanics and Rock Engineering, Vol. 49, No. 12, pp. 4853-4867.
10.1007/s00603-016-1076-z
10
Xiao, J., Huang, G. (2010). “Transverse earthquake response and design analysis of submerged floating tunnels with various shore connections”, Procedia Engineering, Vol. 4, pp. 233-242.
10.1016/j.proeng.2010.08.027
11
Yan, H., Yuqi, L., Jianxing, Y. (2016), “Dynamic response of submerged floating tunnel in the flow field”, Procedia Engineering, Vol. 166, pp. 107-117.
10.1016/j.proeng.2016.11.573
12
Youshi, H., Fei, G. (2010). “Dynamic response and structural integrity of submerged floating”, Procedia Engineering, Vol. 4, pp. 35-50.
10.1016/j.proeng.2010.08.006
13
Zhang, K., Xiang, Y., Du, Y. (2010). “Research on tubular segment design of submerged floating tunnel”, Procedia Engineering, Vol. 4, pp. 199-205.
10.1016/j.proeng.2010.08.023
14
Zhou, X., Wang, Z., Fan, Y., Pan, J. (2012), “Safety study on connection joint for submerged floating tunnel”, Applied Mechanics and Materials, Trans Tech Publications, Vol. 170, pp. 1708-1711.
10.4028/www.scientific.net/AMM.170-173.1708
15
Zingg, S., Anagnostou, G. (2012). “Tunnel face stability in narrow water-bearing fault zones”, Proceedings of the EUROCK 2012, the 2012 ISRM International Symposium-Rock Engineering and Technology for Sustainable Underground Construction, Zürich, pp. 1-11.
Information
  • Publisher :Korean Tunneling and Underground Space Association
  • Publisher(Ko) :한국터널지하공간학회
  • Journal Title :Journal of Korean Tunnelling and Underground Space Association
  • Journal Title(Ko) :한국터널지하공간학회 논문집
  • Volume : 22
  • No :1
  • Pages :77-89
  • Received Date : 2019-12-03
  • Revised Date : 2019-12-16
  • Accepted Date : 2019-12-20
  • DOI :https://doi.org/10.9711/KTAJ.2020.22.1.077
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