Journal of the Korean Geosynthetics Society (한국지반신소재학회논문집)

Korean Geosynthetics Society (한국지반신소재학회)
권호 표지
DOI QR코드

DOI QR Code

Study on Structural Stability Analysis of Excavation Stage Considering Excavation Process and Supporting Materials in Room-and-Pillar Underground Space

격자형 지하공간에서 굴착 공정과 지보재를 고려한 굴착 단계별 구조 안정성 해석 연구

  • Soon-Wook, Choi (Department of Geotechnical Engineering Research, Korea Institute of Civil Engineering and Building Technology) ;
  • Soo-Ho, Chang (Department of Geotechnical Engineering Research, Korea Institute of Civil Engineering and Building Technology) ;
  • Tae-Ho, Kang (Department of Geotechnical Engineering Research, Korea Institute of Civil Engineering and Building Technology) ;
  • Chulho, Lee (Department of Geotechnical Engineering Research, Korea Institute of Civil Engineering and Building Technology)
  • Received : 2022.11.29
  • Accepted : 2022.12.14
  • Published : 2022.12.30
Download PDF
⟨ Previous Next ⟩

Abstract

The room-and-pillar method or grid-type underground space is a method of forming a space by excavating the excavation part at regular intervals so that it is orthogonal and using natural rock mass as a structure. Such excavation may appear different in size from the excavation stage where the maximum displacement occurs depending on the excavation direction and sequence. In this study, considering the installation of support materials such as shotcrete and rock bolts for the optimal design of the excavation process, the safety and constructability of the design and construction of the grid-type underground space under specific ground conditions were analytically reviewed. The ground conditions were set using an numerical method, and the stress at pillar and displacement at center of room were considered for each excavation stage and construction type under a constant surcharge. The height of the space was 8m, which was set higher than the size of a general office, and was reviewed in consideration of equipment and plant facilities. In addition, the degree of displacement control according to the installation of support materials was reviewed in consideration of shotcrete and rock bolts.

주방식 공법(room-and-pillar method) 또는 격자형 지하공간은 굴착부를 일정한 간격으로 직교하도록 굴착하여 자연 암반을 구조체로 활용하여 공간을 형성해 나가는 공법을 말한다. 이러한 굴착은 굴착 방향과 순서에 따라 최대 변위가 발생하는 굴착 단계와 크기가 다르게 나타날 수 있다. 본 연구에서는 격자형 굴착공정의 최적 설계를 위하여 숏크리트 및 록볼트 등 지보재가 설치되는 것을 고려하여 특정 지반조건에서의 격자형 지하공간 설계 및 시공 시 안정성과 시공성을 해석적으로 검토하였다. 해석적 방법을 사용하여 지반조건을 설정하고 일정 상재하중 하에서 굴착단계와 시공 종류별로 암주 응력과 천단 변위를 확인하였다. 공간의 높이는 8m로 일반 사무실 크기보다 높게 설정하여 장비나 플랜트 시설을 감안하여 검토되었다. 또한, 숏크리트와 록볼트를 고려하여 지보재 설치에 따른 변위 제어의 정도를 검토하였다.

Keywords

Acknowledgement

This research was supported by the Korea Agency for Infrastructure Technology Advancement under the Ministry of Land, Infrastructure and Transport of the Korean government (Project Number: 22UGCP-B157945-03).

References

  1. Darling, P. (2011), Mining Engineering handbook, Society for Mining, Metallurgy and Exploration, INC.(SME), 3rd Edition.
  2. Ham, H. S., Park, C. M., Lee, C. and Kim, Y. (2021), "A study on the effect of ground conditions of room and pillar method on pillar and room strain", J. of Korean Tunn Undergr Sp Assoc, Vol.23, No.6, pp.577-587.
  3. Hartman, H. L. and Mutmansky, J. M. (2002), Introductory Mining Engineering. 2nd edition, Wiley, New Jersey.
  4. Lee, C., Hur, J., Hyun, Y. and Chang, S-H. (2014b), "Consideration on design procedure of room-and-pillar underground structure part II: selection of shape to design supports", J. of Korean Tunn Undergr Sp Assoc, Vol.16, No.5, pp.497-506. https://doi.org/10.9711/KTAJ.2014.16.5.497
  5. Lee, C., Hwang, J., Kim, E. and Chang, S-H. (2014a), "Consideration on design procedure of room-and-pillar underground structure part I: parametric study", J. of Korean Tunn Undergr Sp Assoc, Vol.16, No.5, pp.487-495. https://doi.org/10.9711/KTAJ.2014.16.5.487
  6. Lee, C., Hyun, Y., Song, J. and Chang, S-H. (2015), "A preliminary study on the excavation sequence of a room-and-pillar underground structure by the drill-and-blast method", J. of Korean Tunn Undergr Sp Assoc, Vol.17, No.6, pp.605-614. https://doi.org/10.9711/KTAJ.2015.17.6.605
  7. Seoul Metropolitan (2006), Handbook of ground investigation, Technical Reviewer Office, Seoul, Korea