A preliminary study on economical efficiency of a room-and-pillar excavation method in comparison with 2-arch tunnelling method

2아치 터널 굴착 공법과의 비교를 통한 주방식 굴착 공법의 예비 경제성 검토 연구

  • Lee, Chulho (Geotechnical Engineering Research Division, SOC Research Institute, Korea Institute of Construction Technology) ;
  • Chang, Soo-Ho (Geotechnical Engineering Research Division, SOC Research Institute, Korea Institute of Construction Technology) ;
  • Ahn, Sung-Youll (SYTecEnc Co., Ltd.) ;
  • Shin, Hyu-Soung (Geotechnical Engineering Research Division, SOC Research Institute, Korea Institute of Construction Technology)
  • 이철호 (한국건설기술연구원 SOC성능연구소 Geo-인프라연구실) ;
  • 장수호 (한국건설기술연구원 SOC성능연구소 Geo-인프라연구실) ;
  • 안성율 ((주)사이텍이엔씨) ;
  • 신휴성 (한국건설기술연구원 SOC성능연구소 Geo-인프라연구실)
  • Received : 2013.11.05
  • Accepted : 2013.11.12
  • Published : 2013.11.30


This study aims to investigate an economical efficiency of two excavation methods with respect to the room-and-pillar method for the underground space and conventional excavation method, i.e. 2-arch tunnelling method. For feasibility study, an excavation cost for both room-and-pillar method and 2-arch tunnelling method was estimated when the same space in operation was required. It was assumed that properties of reinforcements and rock were adopted from literatures. However, an excavation shape of the room-and-pillar method was assumed not to be the rectangular shape which is a general type in the room-and-pillar method but to be an arch shape in order to compare with the conventional excavation method (2-arch tunnelling) and to achieve the maximum bearing capacity of the structure during excavation. Consequently, the wider space in use or required and the better condition of rock we assumed, the more economical advantage we have in the room-and-pillar method than the 2-arch tunnelling method.


Grant : 운용 중 공간확장이 가능한 지하 굴착 및 안정화 기술 개발

Supported by : 한국건설기술연구원


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Cited by

  1. A study on drainage system of the room-and-pillar underground structure considering groundwater conditions vol.17, pp.6, 2015,
  2. Design of Unsupported Rock Pillars in a Room-and-Pillar Underground Structure by the Tributary Area Method and the Pillar Strength Estimation vol.24, pp.5, 2014,