- Volume 22 Issue 5
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A study on the effect of support structure of steel rib in partitioning excavation of tunnel
터널 상·하반 분할 굴착 시 강지보재 지지구조 효과에 대한 연구
- Kim, Ki-Hyun (DMEC Co., Ltd.) ;
- Kim, Yeon-Deok (Dept. of Civil Engineering, Hoseo University) ;
- Hwang, Beoung-Hyeon (Dept. of Civil Engineering, Hoseo University) ;
- Choi, Yong-Kyu (Dept. of Civil Engineering, Kyungsung University) ;
- Kim, Sang-Hwan (Dept. of Civil Engineering, Hoseo University)
- Received : 2020.07.27
- Accepted : 2020.08.18
- Published : 2020.09.30
This paper is the result of the study on the effect of the support structure of the tunnel steel rib. In tunnel excavation, the top and bottom half excavation methods result in subsidence of steel rib reinforcement due to insufficient support of steel rib reinforcement when the ground is poor after excavation. The foundation of the steel rib installed in the upper half excavates the bottom part of the base, causing the subsidence to occur due to various effects such as internal load and lateral pressure. As a result, the tunnel is difficult to maintain and its safety is problematic. To solve these problems, steel rib support structures have been developed. For the purpose of verification, the behavior of the supporting structure is verified by model experiments reduced to shotcrete and steel rib material similarity, the numerical analysis of ΔP and ΔP generated by bottom excavation by Terzaghi theoretical equation. As a result, it was found that the support structure of 20.100~198.423 kN is required for the 10~40 m section of the depth for each soil of weathered soil~soft rock. In addition, as a result of the reduced model experiment, a fixed level of 50% steel rib deposit of steel rib support structure was installed. The study shows that the installation of steel rib support structures will compensate for uncertainties and various problems during construction. It is also thought that the installation of steel rib support structure will have many effects such as stability, economy, and air reduction.
- Kim, K.H. (2020), A study on the structure of tunnel steel rib support, Ph.D. Thesis, Kyungsung University, pp. 13-95.
- Korea Rail Network Authority (2010), Seoul metropolitan high speed railway (Suseo-Pyoungtaek) design of roadbed and optimization of concrete lining.
- KS F 2314 (2018), Standard test method for unconfined compression test of soils, National Institute of Technology and Standards, Korea.
- Park, S.C., Kim, S.S., Shin, Y.W., Shin, H.S., Kim, Y.G. (2008), "A numerical study on the analysis of behavior characteristics of inclined tunnel considering the optimum direction of steel rib", Journal of Korean Tunnelling and Underground Space Association, Vol. 10, No. 3, pp. 245-256.
- Terzaghi, K. (1946), Rock defects and loads on tunnel support, Rock Tunneling with Steel Supports, eds. R.V. Proctor and T. White, Commercial Shearing Co., Youngstown, pp. 15-99.
- Tunnel and Underground Space in Korea (2007), Tunnel engineering series 2 tunnel theory and practice, Goomibook, Seoul, pp. 3-4.
- Yang, J.Y., Choe, B.S., Yun, I.B., Im, H.C. (2010), "Reinforcement case of low depth soil tunnels in urban areas", Magazine of Korean Tunnelling and Underground Space Association, Vol. 12, No. 2, pp. 47-56.