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The Characteristics of Long-term Deformation Behavior During Tunnel Excavation in the Pyroclastic Rock

화산쇄설암 구간에서 터널 공사 중 장기변형거동 특성 연구

  • Jang, Sukmyung (Chungbuk Headquaters, Korea Expressway Corporation) ;
  • Han, Heuisoo (Dept. of Civil Engineering, Kumoh National Institute of Technology)
  • Received : 2022.06.28
  • Accepted : 2022.07.22
  • Published : 2022.08.01

Abstract

In Korea, 70% of the land is mountainous and structures occupy a high proportion in railway and road construction. In particular, in recent years, the construction of high-speed railways and highways for high-speed driving is rapidly increasing. At the same time, the construction of tunnels is also increasing. The number of tunnel construction cases in which long-term deformation occurs after tunnel excavation is completed is increasing. The stability of these tunnel structures depends entirely on the characteristics of the rock surrounding the tunnel excavation. In the case of pyroclastic rock, which is the subject of this study, it is generally vulnerable to weathering and has a characteristic that its strength decreases over a long period of time. Tunnel design and construction planning considering the strength characteristics of pyroclastic rocks are essential. This study analyzed the cases of over-deformation that occurred at the tunnel site in the pyroclastic section. Based on this study, a plan for tunnel design and construction management in an area where pyroclastic rock exist in the future is presented.

우리나라 지형조건은 산악이 70%를 차지하고 있어 철도 및 도로공사 시 구조물이 차지하는 비중이 높다. 특히, 최근 들어 고속주행을 위한 고속철도와 고속도로 건설이 급증하고 있고 이와 더불어 터널 건설도 증가하고 있고 터널 굴착 완료 후 장기변형이 발생하는 터널 시공사례가 증가하는 추세이다. 이러한 터널 구조물의 안정성은 터널 굴착 주변 암반특성에 전적으로 좌우된다. 본 연구에서 대상인 화산쇄설암의 경우, 전반적으로 풍화에 취약하고 장기간에 걸쳐 강도가 저하되는 특성이 있어서 이를 고려한 터널 설계 및 시공계획 수립이 반드시 필요하다. 본 연구는 화산쇄설암 구간에 터널 현장에서 발생 된 과다변형 사례를 분석하여 향후 화산쇄설암 구간에서는 인버트 설치 및 하부보강을 고려한 방안을 제시하였다.

Keywords

References

  1. Jang, Y.C., Kim, N.Y., Jin, K.D. and Son, Y.M. (2014), Upheaveal behaviour of tunnel bottom in the weatherd fracture zone under tunnel excavation, Journal fo the Korean Geoenviron-metal Society, Vol. 15, No. 6, pp. 49~56 (In Korean).
  2. Kim, N.Y. and Lee, K.H. (2019), Technical Advisory Report, Korea Expressway Corporation Research Institute, pp. 21~78 (In Korean).
  3. Song, G.I. and Yun, J.S. (2016), Tunnel Deformation Mechanism, pp. 79~85 (In Korean).