Journal of Korean Tunnelling and Underground Space Association (한국터널지하공간학회 논문집)

Korean Tunnelling and Underground Space Association (한국터널지하공간학회)
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A study on the clogging of shield TBM cutterhead opening area according to the characteristics of cohesive soil content

점성토 함량 특성에 따른 shield TBM cutterhead 개구부의 폐색현상에 관한 연구

  • Received : 2021.01.28
  • Accepted : 2021.07.20
  • Published : 2021.07.31
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Abstract

Population density due to urbanization is making people interested in underground space development and much interest in TBM construction with low vibration and noise. This led to a lot of research on TBM. However, research on the characteristics of the cutterhead opening of the TBM equipment being occluded under the ground conditions under which it is excavated is insufficient. Accordingly, a study was conducted to investigate clogging of the cutterhead opening during the shield TBM rolling. To identify the clogging of cutterhead openings in SHIELD TBM equipment, the reduced model experiment was divided into clay rate (10%, 30%, 50%, 60%), cutterhead opening rate (30%, 50%, 60%), and cutterhead rotation direction (one-way, two-way) and rotational speed (3 RPM) and conducted in 36 cases. Results of scale model test on shield TBM clogging, it was analyzed that the ground condition containing clay soil increased the clogging effect in both directions than the unidirectional rotation, and that the lower the rotational speed of the cutterhead, the less the clogging effect. Accordingly, the direction of cutterhead rotation, rotational speed and opening rate are calculated by taking into account ground conditions during ground excavation, the clogging effect can be reduced. It is believed to be effective in saving air as the clogging effect is reduced. Therefore, this study is expected to be an important material for domestic use of shield TBM.

도시화로 인한 인구의 집중은 도심지 지하공간 개발을 촉발시켰으며, 그로인해 진동과 소음으로 인한 환경문제 및 민원이 많은 발파공법보다 진동과 소음에 대한 영향이 없는 TBM공법에 많은 관심을 가지게 되었다. 이런 이유로 TBM에 대한 많은 연구가 진행되었으나 TBM 장비의 커터헤드 개구부가 굴착되는 지반조건에 따라 폐색되는 특성에 대한 연구는 미비한 실정이다. 그렇기 때문에 쉴드 TBM 굴진 시 커터헤드 개구부의 폐색현상을 연구하기 위해 축소모형시험을 진행하였다. 쉴드 TBM 장비의 커터헤드 개구부 폐색현상을 규명하기 위해 점토비(10%, 30%, 50%), 커터헤드 개구율(30%, 50%, 60%), 커터헤드 회전방향(일방향, 양방향) 및 회전속도(3 RPM, 6 RPM)을 변수로 실험조건을 달리하여 36가지의 Case에 대해 축소모형실험을 진행하였다. 쉴드 TBM 폐색현상에 대한 축소모형실험 결과, 점토가 함유된 지반 조건은 양방향 회전이 일방향 회전보다 폐색영향이 증가하고 커터헤드의 회전속도가 낮을수록 폐색영향이 적은 것으로 나타났다. 그에 따라 지반 굴착 시 지반조건을 고려하여 커터헤드 회전 방향, 회전 속도 및 개구율을 산정한다면 폐색 영향을 저감할 수 있을 것이다. 폐색영향이 저감됨에 따라 공사기간의 단축에 효과적일 것으로 사료된다. 따라서 본 연구는 해당연구가 전무한 국내 쉴드 TBM 시공 시 그 활용에 있어 중요한 자료가 될 것으로 판단된다.

Keywords

Acknowledgement

본 연구는 한국연구재단의 이공분야 기초연구사업(Shield TBM 배토처리 향상을 위한 Soil conditioning 기술 개발, NRF-2018R1A2B6002725) 지원으로 수행되었으며 이에 깊은 감사를 드립니다.

References

  1. Chang, S.H., Choi, S.W., Park, Y.T., Lee, G.P., Bae, G.J. (2013), "Experimental evaluation of the effects of cutting ring shape on cutter acting forces in a hard rock", Journal of Korean Tunnelling and Underground Space Association, Vol. 15, No. 3, pp. 225-235. https://doi.org/10.9711/KTAJ.2013.15.3.225
  2. Cho, J.W., Yu, S.H., Jeon, S.W., Chang, S.H. (2008), "Numerical study on rock fragmentation by TBM disc cutter", Journal of Korean Tunnelling and Underground Space Association, Vol. 10, No. 2, pp. 139-152.
  3. Hwang, B.H., Kim, S.H., Lee, K.H., An, J.K., Cho, S.W., Kim, Y.D. (2020), "A basic study on the mixing bar interaction efficiency in shield TBM chamber", Journal of Korean Tunnelling and Underground Space Association, Vol. 22, No. 1, pp. 91-105. https://doi.org/10.9711/KTAJ.2020.22.1.091
  4. Kang, E.M., Kim, Y.M., Hwang, I.J., Kim, S.H. (2015), "A study on the damage of cutter bit due to the rotation speed of shield TBM cutter head in mixed ground", Journal of Korean Tunnelling and Underground Space Association, Vol. 17, No. 3, pp. 403-413. https://doi.org/10.9711/KTAJ.2015.17.3.403
  5. Kong, M.T., Kim, Y.D., Lee, K.H., Hwang, B.H., An, J.K., Kim, S.H. (2019), "Development of shield-TBM scale model system for excavation of curved section", Journal of Korean Tunnelling and Underground Space Association, Vol. 21, No. 6, pp. 849-860. https://doi.org/10.9711/KTAJ.2019.21.6.849
  6. KS F 2303 (2015), Standard test method for liquid limit and plastic limit of soils, National Institute of Technology and Standards, Korea.
  7. KS F 2312 (2016), Standard test method for soil compaction, National Institute of Technology and Standards, Korea.
  8. Sugimoto, M., Sramoon, A., Konishi, S., Sato, Y. (2007), "Simulation of shield tunneling behavior along a curved alignment in a multilayered ground", Journal of Geotechnical and Geoenvironmental Engineering, Vol. 133, No. 6, pp. 684-694. https://doi.org/10.1061/(ASCE)1090-0241(2007)133:6(684)
  9. Thewes, M., Burger, W. (2005), "Clogging of TBM drives in clay - identification and mitigation of risks", Underground Space, pp. 737-742.
  10. Hollmann, F.S., Thewes, M. (2013), "Assessment method for clay clogging and disintegration of fines in mechanised tunneling", Tunnelling and Underground space Technology, Vol. 37, pp. 96-106. https://doi.org/10.1016/j.tust.2013.03.010