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DEM-based numerical study on discharge behavior of EPB-TBM screw conveyor for rock

EPB-TBM 암반굴착시 스크류컨베이어의 배토 거동에 대한 DEM 기반 수치해석적 연구

  • Lee, Gi-Jun (Dept. of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST)) ;
  • Kwon, Tae-Hyuk (Dept. of Civil and Environmental Engineering, Korea Advanced Institute of Science and Technology (KAIST)) ;
  • Kim, Huntae (R&D Center (TBM Technical Team), Head Office, Energy & Machinery Korea)
  • 이기준 (한국과학기술원 건설 및 환경공학과) ;
  • 권태혁 (한국과학기술원 건설 및 환경공학과) ;
  • 김훈태 (이엠코리아 본사 연구소(TBM기술팀))
  • Received : 2018.11.27
  • Accepted : 2018.12.11
  • Published : 2019.01.31

Abstract

Tunnel construction by TBMs should be supported by the performance of a screw conveyor in order to obtain the optimum penetration rate, so studies related to the screw conveyor performance have been being conducted. Compared to the study on the performance of the screw conveyor for the soil, however, the research on the performance of the screw conveyor for the rock is insufficient. Considering the domestic tunnel sites with more rock layers than soil layers, simulation of discharge of 6 types of rock chips by the screw conveyor was conducted using DEM. Regardless of the shape and volume of the rock chips, the discharge rates of the rock chips by the parallel placed screw conveyor at a speed of 10 RPM in the same rock mass were about 20% (standard deviation: 1.3%) of the maximum volume of discharge rate by the screw conveyor. It is expected that this study can be used as a reference material for screw conveyor design and operation in TBM excavations in rock masses.

TBM 터널공사 시 스크류컨베이어의 배토 거동에 대한 이해는 굴진율 향상을 위한 중요한 요소이다. 본 연구에서는 지반에서 디스크 커터에 의해 생성되는 암반칩의 형상에 따라 스크류컨베이어 내부에서의 이동 및 배토 거동에 대한 연구를 수행하였다. 입자기반의 DEM 수치해석기법을 이용하여, 6가지의 대표적인 모양에 대한 암반칩을 클러스터로 형성하였다. 또한, 실제 스크류컨베이어의 3D 축소모델을 형성한 후, 다른 모양의 암반칩의 시간당 배토량을 측정 하였다. 시뮬레이션 결과, 스크류컨베이어의 경사각이 $0^{\circ}$일 때, 동일한 암반에서 암반칩의 형상과 부피와 상관없이 10 RPM 속도에서의 스크류컨베이어 배토량은 스크류컨베이어 최대 배토량의 약 20%로 나타났다(표준편차: 1.3%). 본 연구 결과는 암반용 TBM 설계 및 암반에서의 TBM 굴착 시 스크류컨베이어 운용에 참고할 수 있는 자료로 사용될 수 있을 것으로 예상된다.

Keywords

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Fig. 1. Simulation of discharge of rock chips by screw conveyor

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Fig. 2. Number of discharged rock chips by DEM simulation

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Fig. 3. Discharge volume of rock chips by DEM simulation

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Fig. 4. Screw conveyor DEM simulation for discharge of rock chip 2 and 6 after 24 seconds

Table 1. Rock chip models

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Table 2. Geometry information

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Table 3. Simulation parameters

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Table 4. Discharged particle rate

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Table 5. Discharge rates of rock chips

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Acknowledgement

Grant : 도심지 소단면(

Supported by : 국토교통과학기술진흥원

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