DOI QR코드

DOI QR Code

A study on the soil conditioning behaviour according to mixing method in EPB shield TBM chamber

EPB 쉴드 TBM 챔버 내 혼합방법에 따른 배토상태거동에 대한 연구

  • 김연덕 (유광토건 기술연구소) ;
  • 황병현 (호서대학교 토목공학과) ;
  • 조성우 (호서대학교 토목공학과) ;
  • 김상환 (호서대학교 토목공학과)
  • Received : 2021.03.29
  • Accepted : 2021.07.19
  • Published : 2021.07.31

Abstract

This paper is a study to improve the efficiency of mixing technology in the shield TBM chamber. Currently, the number of construction cases using the TBM method is increasing in Korea. According to the increasing use of TBM method, research on TBM method such as Disc Cutter, Cutter bit, and Segment also shows an increasing trend. However, there is little research on the mixing efficiency in chamber and chamber. In order to improve the smooth soil treatment and the behavior of the excavated soil, a study was conducted on the change of the mixing efficiency according to the effective mixing bar arrangement in the chamber. In the scale model experiment, the ground was composed using plastic materials of different colors for ease of identification. In addition, the mixing bar arrangement was different and classified into 4 cases, and the particle size distribution was classified into single particle size and multiple particle size, and the experiment was conducted with a total of 8 cases. The rotation speed of the cutter head of all cases was the same as 5 RPM, and the experiment time was also carried out in the same condition, 1 minute and 30 seconds. In order to check the mixing efficiency, samples at the upper, middle (left or right), and lower positions of each case were collected and analyzed. As a result of the scaled-down model experiment, the mixing efficiency of Case 4 and Case 4-1 increased compared to Case 1 and Case 1-1, which are actually used. Accordingly, it is expected that the mixing efficiency can be increased by changing the arrangement of the mixing bar in the chamber, and it is considered to be effective in saving air as the mixing efficiency increases. Therefore, this study is considered to be an important indicator for the use of shield TBM in Korea.

본논문은 쉴드 TBM 챔버(Chamber) 내 배토처리 효율성 향상을 위한 연구이다. 현재 국내에서는 TBM 공법을 이용한 시공사례가 증가하는 추세이다. TBM 공법 사용의 증가에 따른 디스크 커터(Disc Cutter), 커터 비트(Cutter bit) 및 세그먼트와 같은 TBM 공법의 연구 또한 증가하는 추세를 보인다. 하지만 챔버와 챔버 내 교반 성능에 대한 연구는 미비한 실정이다. 원활한 배토처리와 굴착토의 거동을 개선하기 위하여 챔버 내 효과적인 믹싱 바 배치에 따른 교반 효율 변화에 대한 연구를 수행하였다. 축소모형 실험은 식별의 용이성을 위하여 색이 다른 플라스틱 소재를 사용하여 지반을 조성하였다. 또한 믹싱 바 배치를 상이하게 하여 4가지 Case로 분류하였으며, 입도분포를 단입도와 다입도로 분류하여 총 8가지의 Case로 실험을 진행하였다. 모든 Case의 커터헤드의 회전속도는 5 RPM으로 동일하며, 실험시간 또한 동일한 조건인 1분 30초로 진행하였다. 교반 효율을 확인하기 위하여 각 Case별 상부, 중부(좌 or 우), 하부 위치의 시료를 채취하여 분석하였다. 축소모형실험 결과 실제 사용되는 Case 1과 Case 1-1보다 새로운 배치방법인 Case 4와 Case 4-1의 교반 효율이 증가하는 양상을 보인다. 그에 따라 챔버 내 믹싱 바 배치를 변경하여 교반 효율을 증가시킬 수 있을 것으로 보이며, 교반 효율증가에 따라 공기 절약에 효과적일 것으로 판단된다. 따라서 본 연구는 국내 쉴드 TBM 공법 활용에 있어 큰 지표로써 작용할 것으로 보인다.

Keywords

Acknowledgement

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

References

  1. 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.
  2. Chang, S.H. (2015), "A consideration for mechanical rock excavation focusing on TBM and roadheader", Journal of the Korean Society of Mineral and Energy Resources Engineers, Vol. 52, No. 5, pp. 531-548. https://doi.org/10.12972/ksmer.2015.52.5.531
  3. Ham, S.K., Jung, H., Kim, B.J., Jeong, K.H., Lee, S.W. (2020), "Waterproofing performance evaluation according to the number of layer for shield TBM segment hydrophilic rubber waterstop", Journal of Korean Tunnelling and Underground Space Association, Vol. 22, No. 1, pp. 47-58. https://doi.org/10.9711/KTAJ.2020.22.1.047
  4. 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
  5. Kim, S.H., Oh, T.S., Park, S.H., Lee, C.Y., Park, J.K. (2014), "Development of simulation equipment system on EPB shield TBM hood operation", Journal of Korean Tunnelling and Underground Space Association, Vol. 16, No. 2, pp. 193-201. https://doi.org/10.9711/KTAJ.2014.16.2.193
  6. Kim, W.S. (2020), A study on chamber pressure of EPB shield TBM with measurement data analysis of under the river, Doctorate Student Thesis, Woosong University, pp. 6-8.
  7. Park, H.K., Chang, S.B., Lee, S.B. (2015), "A study of shield TBM tunnelling-induced volume loss estimation considering shield machine configurations and driving data", Tunnel and Underground Space, Vol. 25, No. 5, pp. 397-407. https://doi.org/10.7474/TUS.2015.25.5.397
  8. Sagong, M., Jung, C.K., Moon, J.B., Kim, J.Y., Yun, D.S., Yu, M.H (2015), "A manual for the revised TBM tunnel specification", Journal of Korean Tunnelling and Underground Space Association, Vol. 17, No. 4, pp. 415-428. https://doi.org/10.9711/KTAJ.2015.17.4.415
  9. Yoon, D.H., Song, J.J. (2019), "Review on design of underground mine openings in Korea and overseas", Tunnel and Underground Space, Vol. 29, No. 1, pp. 30-37. https://doi.org/10.7474/TUS.2019.29.1.030
  10. You, S.H., Chang, S.H., Cho, J.W., Jeon, S.W. (2008), "Estimation of the optimum TBM disc cutter spacing by the dynamic fracture modeling", Journal of Korean Tunnelling and Underground Space Association, Vol. 10, No. 1, pp. 81-90.