Analysis of Advanced Rate and Downtime of a Shield TBM Encountering Mixed Ground and Fault Zone: A Case Study

Hoyoung Jeong; Mincheol Kim; Minwoo Lee; Seokwon Jeon

doi:10.7474/TUS.2019.29.6.394

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2019 Vol.29, Issue 6 Preview Page Next Page

Case Study

Analysis of Advanced Rate and Downtime of a Shield TBM Encountering Mixed Ground and Fault Zone: A Case Study 단층대와 복합지반을 통과하는 쉴드TBM의 굴진율 및 다운타임 발생 특성 분석

31 December 2019. pp. 394-406

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Abstract

Difficult ground conditions (e.g., fault zone and mixed grounds) are highly probable to appear in subsea and urban tunnels because of the shallow working depth and alluvial characteristics. TBM usually experienced decrease of penetration rate and increase of downtime when it meets these difficult ground conditions. The problems are usually caused by the adverse geological conditions, and it is preferable to determine the optimal operational parameters of TBM based on the previous operational data obtained while excavating a preceding tunnel. This study carried out for efficient TBM excavation in fault zone and mixed grounds. TBM excavation data from the tunnel site in Singapore and the characteristics of the TBM excavation data was analyzed. The key operational parameters (i.e., thrust, torque, and RPM), penetration rate, and downtime were highly influenced by the presence of fault zones and mixed grounds, and the features was discussed. It is expected that the results and main discussions will be useful information for future tunneling projects in similar geological conditions.

Keywords

Fault zone

Mixed ground

Shield TBM

Penetration rate

Downtime

도심지와 하･해저 터널에서는 연약지반 혹은 특수지반(단층대, 복합지반 등)을 조우할 가능성이 높으며, 이러한 조건에서는 TBM의 굴진율이 저하되고 다운타임이 증가하는 등의 문제점이 발생한다. 이러한 문제점들은 지반조사에서 발견되지 않은 불리한 지반조건에 기인하는 경우가 많으며, 굴진 중 수집된 굴진데이터를 근거로 향후 지층조건에 대한 최적의 운용조건을 결정하는 것이 최선이다. 본 연구는 향후 쉴드 TBM을 이용한 터널공사에서 단층대 및 복합지반에서의 효율적인 시공을 위하여 수행되었다. 외국의 사례를 통해 수집된 TBM의 굴진데이터를 활용하여 굴진율과 다운타임 발생 특성을 지층조건에 따라 분석하였다. 추력, 토크, RPM 등 주요 TBM의 기계데이터와 굴진율, 다운타임은 단층대와 복합지반의 특징에 따라 크게 영향을 받는 것을 확인하였고, 그 특징에 대하여 논하였다. 향후 국내외 유사한 지반에서의 TBM 시공 시 유용하게 활용될 수 있을 것으로 기대된다.

키워드

단층대

복합지반

쉴드 TBM

굴진율

다운타임

References

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Information

Publisher :Korean Society for Rock Mechanics and Rock Engineering
Publisher(Ko) :한국암반공학회
Journal Title :Tunnel and Underground Space
Journal Title(Ko) :터널과 지하공간
Volume : 29
No :6
Pages :394-406
Received Date : 2019-12-10
Revised Date : 2019-12-16
Accepted Date : 2019-12-17
DOI :https://doi.org/10.7474/TUS.2019.29.6.394

Tunnel and Underground Space ISSN:1225-1275(Print) 2287-1748(Online) 터널과 지하공간

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