All Issue

2018 Vol.20, Issue 5 Preview Page
A numerical study on the 3-Dimensional shape characteristics of small underground cavities

소규모 지하공동 3차원 형상 특성을 반영한 수치해석에 관한 연구

Joon-Sang An1
,
Kyung-Nam Kang2
,
Ki-Il Song3
,
Woo-Seok Kim4
,
Byung-Chan Kim5*
안 준상1
,
강 경남2
,
송 기일3
,
김 우석4
,
김 병찬5*
1Head Researcher, Construction IT Laboratory, BasisSoft, Inc.
2Graduate Student, Dept. of Civil Engineering, Inha University
3Associate Professor, Dept. of Civil Engineering, Inha University
4Senior Researcher, Dept. of Infrastructure Safety Research, KICT
5Chief Researcher, Construction IT Laboratory, BasisSoft, Inc.
1(주)베이시스소프트 건설IT연구소 수석연구원
2인하대학교 토목공학과 석사과정
3인하대학교 토목공학과 부교수
4한국건설기술연구원 인프라안전연구본부 수석연구원
5(주)베이시스소프트 건설IT연구소 연구소장
* Corresponding Author
30 September 2018. pp. 787-807
PDF XML Citation
Abstract

When conducting the underground safety impact assessment under the special law in Korea, it is essential to investigate the occurrence of underground cavities. When underground cavities were discovered, the underground safety was assessed through numerical analysis. The previous study has suggested the stability evaluation based on the factor of safety by changing the 2D shape of the small underground cavity. In this study, the effects of small underground cavities considering 3D shapes were examined using a continuum analysis program and compared with the 2D results presented in previous study. If the 3-Dimensional shape of the underground cavity is found close to the sphere type, it would be reasonable to evaluate the factor of safety by the shear strength reduction method regardless of the size and position of the cavity. If a high-aspect ratio underground cavity with a depth of 2 m or more from the ground surface and an aspect ratio (a/b) of 2.0 or more is in the vertical direction, not only the factor of safety but the failure mode shape should be cautions in the stability evaluation using the shear strength reduction method. The results of this study are expected to be basic data on underground safety impact assessment.

Keywords
Small underground cavity
Numerical analysis
Ground subsidence
Shear strength reduction method (SSR)

한국에서 시행중인 특별법에 의한 지하안전영향 평가 수행 시, 필수적으로 지하공동의 발생 유무를 조사하여야 한다. 지하공동 발견 시에는 수치해석을 통해서 지하안전성을 평가하도록 규정하였다. 선행 연구를 통해서 소규모 지하공동의 2차원 형상변화를 통한 안전율 기반의 안정성 평가 가능성을 제시하였다. 본 연구에서는 3차원 형상을 고려하여 소규모 지하공동의 영향을 연속체 해석 프로그램을 사용해서 검토하였고, 선행 연구에서 제시한 2차원 해석결과와 비교하였다. 지하공동의 3차원 형상이 구(sphere)형에 가깝게 발견되면, 공동의 크기, 위치 등에 관계없이 전단강도감소기법으로 안전율을 산정하여 평가하는 방법에 무리가 없을 것으로 판단된다. 지표면으로부터의 깊이 2 m 이상, 장축과 단축의 비(a/b)가 2.0 이상인 장대형 지하공동이 연직방향으로 서있는 형상이라면, 전단강도감소기법을 사용한 안정성 평가에 안전율 이외에 파괴양상 파악에도 주의가 필요할 것으로 판단된다. 본 연구의 결과는 지하안전영향평가에 관한 기초 자료가 될 수 있을 것으로 판단된다.

키워드
소규모 지하공동
수치해석
지반함몰
전단강도감소기법
References
1
An, J.S., Kang, K.N., Song, K.I., Kim, B.C. (2018), “A numerical study on the characteristics of small underground cavities in the surrounding old water supply and sewer pipeline”, Journal of Korean Tunnelling and Underground Space Association, Vol. 20, No. 2, pp. 287-303.
2
Arellano, D., Stark, T.D. (2000), “Importance of three-dimensional slope stability analyses in practice”, In Slope Stability 2000, pp. 18-32.
10.1061/40512(289)2
3
Bergado, D.T., Teerawattanasuk, C. (2008), “2D and 3D numerical simulations of reinforced embankments on soft ground”, Geotextiles and Geomembranes, Vol. 26, No. 1, pp. 39-55.
10.1016/j.geotexmem.2007.03.003
4
Choi, S.K., Back, S.H., An, J.B., Kwon, T.H. (2016), “Geotechnical investigation on causes and mitigation of ground subsidence during underground structure construction”, Journal of Korean Tunnelling and Underground Space Association, Vol. 18, No. 2, pp. 143-154.
10.9711/KTAJ.2016.18.2.143
5
Dhawan, K.R., Singh, D.N., Gupta, I.D. (2002), “2D and 3D finite element analysis of underground openings in an inhomogeneous rock mass”, International Journal of Rock Mechanics and Mining Sciences, Vol. 39, No. 2, pp. 217-227.
10.1016/S1365-1609(02)00020-5
6
Drumm, E.C., Aktürk, Ö., Akgün, H., Tutluoğlu, L. (2009), “Stability charts for the collapse of residual soil in karst”, Journal of Geotechnical and Geoenvironmental Engineering, Vol. 135, No. 7, pp. 925-931.
10.1061/(ASCE)GT.1943-5606.0000066
7
Hoek, E., Brown, E.T. (1980), “Underground excavations in rock”, (No. Monograph).
8
Hungr, O., Salgado, F.M., Byrne, P.M. (1989), “Evaluation of a three-dimensional method of slope stability analysis”, Canadian Geotechnical Journal, Vol. 26, No. 4, pp. 679-686.
10.1139/t89-079
9
Itasca Consulting Group, Inc. (2012), FLAC3D-Fast Lagrangian Analysis of Continua in 3 Dimensions, Version 5.0, User Manual, Minnesota, USA.
10
Kim, J.B., You, S.K., Han, J.K., Kim, Y.H. (2017), “Experimental study on generating mechanism of the ground subsidence of due to damaged waters supply pipe”, Proceedings of the 2017 Spring Geosynthetics Conference, pp. 46-47.
11
Kim, J.K. (2014), Study on stress state and support for limestone mines excavated room & pillar method, Ph.D. Thesis, Department of Energy and Resources Engineering, Graduate School, Chonnam National University, pp. 15-19.
12
Kim, S.J. (2013), Stability analysis of the inclined pillars by statistical analysis, Master’s Thesis, Department of Energy and Resources Engineering, Graduate School, Chonnam National University, pp. 20-22.
13
Lee, D.Y., Cho, N.K. (2016), “DEM modelling of underground cavity due to sewer pipe leakage”, Proceedings of the 2016 Fall Geosynthetics Conference, pp. 103-104.
14
Lee, J.H., Jin, H.S., Baek, Y., Yoon, H.S. (2017), “Evaluation of land subsidence risk depending on grain size and verification using numerical analysis”, The Journal of Engineering Geology, Vol. 27, No. 2, pp. 133-141.
15
Lee, J.H., Lee, Y.J. (2014), “Analysis of ground behavior for model tunnel excavation with pipe roof reinforcement using close range photogrammetric technique”, Journal of Korean Tunnelling and Underground Space Association, Vol. 16, No. 4, pp. 387-402.
10.9711/KTAJ.2014.16.4.387
16
Lee, S.H. (2017), The life cycle informatization and structural stability analysis for double-deck tunnel, Master’s Thesis, Department of Civil Engineering, Graduate School, Inha University, pp. 37-52.
17
Rujikiatkamjorn, C., Indraratna, B., Chu, J. (2008), “2D and 3D numerical modeling of combined surcharge and vacuum preloading with vertical drains”, International Journal of Geomechanics, Vol. 8, No. 2, pp. 144-156.
10.1061/(ASCE)1532-3641(2008)8:2(144)
18
Seoul Metropolitan Government (2014), Announcement of special management measures for road subsidence in Seoul, http://infra.seoul.go.kr/archives/17649?tr_code=sweb.
19
Song, W.K., Chung, S.K., Han, K.C. (2002), “Stability analysis of a tunnel above mined cavities”, Journal of Korean Tunnelling and Underground Space Association, Vol. 4, No. 2, pp. 135-141.
20
Park, J.Y., Son, J.H., Park, K.L., Oh, Y.S. (2012), “A study on damage mechanism of transition section in cut and cover tunnel using 3 dimensional numerical analysis”, Journal of Korean Tunnelling and Underground Space Association, Vol. 14, No. 6, pp. 653-666.
10.9711/KTAJ.2012.14.6.653
21
Park, Y.J., You, K.H. (1998), “Stability analysis for jointed rock slope using ubiquitous joint model”, Tunnel & Underground, Journal of Korean Society for Rock Mechanics, Vol. 8, No. 4, pp. 287-295.
22
You, K.H., Park, Y.J., Kang, Y. (2001), “A numerical study on the estimation of safety factor of tunnels excavated in jointed rock mass”, Tunnel and Underground Space, Vol. 11, No. 3, pp. 279-288.
Information
  • Publisher :Korean Tunneling and Underground Space Association
  • Publisher(Ko) :한국터널지하공간학회
  • Journal Title :Journal of Korean Tunnelling and Underground Space Association
  • Journal Title(Ko) :한국터널지하공간학회 논문집
  • Volume : 20
  • No :5
  • Pages :787-807
  • Received Date : 2018-06-20
  • Revised Date : 2018-07-24
  • Accepted Date : 2018-07-31
  • DOI :https://doi.org/10.9711/KTAJ.2018.20.5.787
Journal Informaiton Journal of Korean Tunnelling and Underground Space Association Journal of Korean Tunnelling and Underground Space Association
Online Submission & Review System
  • NRF
  • KOFST
  • KISTI Current Status
  • KISTI Cited-by
  • crosscheck
  • orcid
  • open access
  • ccl
Journal Informaiton Journal Informaiton - close