Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
권호 표지
DOI QR코드

DOI QR Code

A Numerical Study on the Occurrence Scope of Underground Cavity and Relaxation Zone Considering Sewerage Damage Width and Soil Depth

하수관거 파손폭과 토피고를 고려한 지중 공동 및 이완영역 발생 규모에 관한 수치해석적 연구

  • You, Seung-Kyong (Dept. of Civil Engrg., Myongji College) ;
  • Ahn, HeeChul (Dept. of Civil Engrg. & Environmental Engrg., Chung-Ang Univ.) ;
  • Kim, Young-Ho (Dept. of Civil Engrg. & Environmental Engrg., Chung-Ang Univ.) ;
  • Han, Jung-Geun (Dept. of Civil Engrg. & Environmental Engrg., Chung-Ang Univ.) ;
  • Hong, Gigwon (Institute of Technology Research and Development, Korea Engineering & Construction) ;
  • Park, Jeong-Jun (Incheon Disaster Prevention Research Center, Incheon Natl. Univ.)
  • 유승경 (명지전문대학 토목공학과) ;
  • 안희철 (중앙대학교 토목공학과) ;
  • 김영호 (중앙대학교 토목공학과) ;
  • 한중근 (중앙대학교 토목공학과) ;
  • 홍기권 ((주)대한건설ENG 기술연구소) ;
  • 박정준 (인천대학교 방재연구센터)
  • Received : 2018.12.17
  • Accepted : 2019.01.22
  • Published : 2019.01.31
Download PDF
⟨ Previous Next ⟩

Abstract

This paper described a result of finite element analysis considering sewerage damage scale and soil depth, in order to analyze quantitatively for cavity and relaxation zone of underground due to sewerage damage. The mechanical model, which was verified by previous studies, was applied to the finite element analysis. In addition, the mechanical behavior of the soil around the sewerage damage due to the soil loss was simulated by using the forced displacement. Based on finite element analysis results, characteristics of the void ratio distribution, ground subsidence, and shear stress distribution according to sewerage damage scale and soil depth were analyzed. And then, The boundaries of the underground cavity and relaxation zone were determined by using the shear stress reduction characteristics of the ground. Also, an occurrence scope of the cavity and relaxation zone was quantitatively evaluated by the change of sewerage damage scale and soil depth.

본 논문에서는 하수관거 파손에 따른 토사 유실로 인해 발생되는 지중 공동 및 이완영역의 규모를 정량적으로 분석하기 위해 하수관거 파손 폭과 하수관거 상부의 토피고 변화를 고려한 유한요소 수치해석을 실시하였다. 수치해석에서는 선행 연구에서 검증된 역학모델을 적용하였으며, 강제변위법을 이용하여 토사 유실에 따른 하수관거 파손부 주변지반의 역학적 거동을 모사하였다. 수치해석 결과로부터 파손 폭 및 토피고 변화에 따른 모형지반의 간극비 분포, 지표면 침하, 전단응력 분포 특성을 분석하였다. 또한, 지중의 전단응력 감소 특성을 분석하여 지중 공동 및 이완영역의 경계를 결정하였으며, 파손 폭과 토피고 변화에 따른 공동 및 이완영역의 발생 규모를 정량적으로 평가하였다.

Keywords

GJBGC4_2019_v35n1_43_f0001.png 이미지

Fig. 1. FEA Model correspond with experimental model test

GJBGC4_2019_v35n1_43_f0002.png 이미지

Fig. 2. Relationship of stress-strain in hardening soil model (Schanz et al., 1999)

GJBGC4_2019_v35n1_43_f0003.png 이미지

Fig. 3. FEA results for evaluation of cavity and relaxation zone in ground

GJBGC4_2019_v35n1_43_f0004.png 이미지

Fig. 4. FEA Model considering sewerage damage width and soil depth

GJBGC4_2019_v35n1_43_f0005.png 이미지

Fig. 5. Void ratio distribution

GJBGC4_2019_v35n1_43_f0006.png 이미지

Fig. 6. Settlement distribution of ground surface

GJBGC4_2019_v35n1_43_f0007.png 이미지

Fig. 7. Variation of maximum settlement on ground surface

GJBGC4_2019_v35n1_43_f0008.png 이미지

Fig. 8. Shear stress distribution

GJBGC4_2019_v35n1_43_f0009.png 이미지

Fig. 9. Distribution of shear stress reduction ratio

GJBGC4_2019_v35n1_43_f0010.png 이미지

Fig. 10. Aspect ratio according to sewerage damage width

GJBGC4_2019_v35n1_43_f0011.png 이미지

Fig. 11. Aspect ratio according to soil depth

Table 1. Soil parameters of hardening soil model in FEA

GJBGC4_2019_v35n1_43_t0001.png 이미지

Table 2. FEA Cases

GJBGC4_2019_v35n1_43_t0002.png 이미지

References

  1. An, J. S., Kang, K. N., Song, K. I., and 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 AssociationJ, Vol.20, No.2, pp.287-303. https://doi.org/10.9711/KTAJ.2018.20.2.287
  2. Bae, Y. S., Kim, K. T., and Lee, S. Y. (2017), "The Road Subsidence Status and Safety Improvement Plans", Journal of the Korea Academia-Industrial cooperation Society, Vol.18, No.1 pp.545-552. https://doi.org/10.5762/KAIS.2017.18.1.545
  3. Benz, T. (2007), Small-Strain Stiffness of Soils and its Numerical Consequences, Ph.D. Thesis, University of Stuttgart.
  4. Choi, Y. W. (2016), "A Study on Identifying and Managing the Mechanism of Generating Cavity Mechanism in Seoul", Korean Geosynthetics Society, Vol.15, No.1, pp.8-10.
  5. Cooper, A. H. (1986), "Subsidence and Foundering of Strata Caused by the Dissolution of Permian Gypsum ing Ripon and Bedale Areas, North Yorkshire", Geological Society, London, Special Publications, Vol.22, No.1, pp.127-139. https://doi.org/10.1144/GSL.SP.1986.022.01.11
  6. Drumm, E. C., Akturk, O., Akgun, H., and Tutluoglu, 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. https://doi.org/10.1061/(ASCE)GT.1943-5606.0000066
  7. Kim, J. B., You, S. K., Han, J. G., Hong, G. G., and Park, J. B. (2017), "A Study on Simulation of Cavity and Relaxation Zone Using Laboratory Model Test and Discrete Element Method", Journal of Korean Geosynthetics Society, Vol.16, No.2, pp.11-21. https://doi.org/10.12814/jkgss.2017.16.2.011
  8. Kim, N. Y. and Umm, T. W. (2013), "A Case Study on the Chimney Collapse of Tunnel under Construction", Proceeding of Korean geo-environmental society, Seoul, pp.43-53.
  9. Korea institute of geoscience and mineral resources (2014), Research on causes and policy suggestions by sinkhole type, Research report, pp.18-39.
  10. Kuwano, R., Sato, M., and Sera, R. (2010), "Study on the Detection of Underground Cavity and Ground Loosening for the Prevention of Ground Cave-in Accident", Japanese Geotechnical Journal, Vol.5, No.2, pp.219-229. https://doi.org/10.3208/jgs.5.219
  11. Lee, K. C., Park, J. H., Choi, B. H., and Kim, D. W. (2018), "Analysis of Influencing Factors on Cavity Collapse and Evaluation of the Existing Cavity Management System", Journal of Korean Geosynthetics Society, Vol.17, No.1, pp.45-54. https://doi.org/10.12814/JKGSS.2018.17.1.045
  12. Lee, S. H., Lee H. L., and Song, K. I. (2016), "The Effect of Formation of Spherical Underground Cavity on Ground Surface Settlement : Numerical Analysis Using 3D DEM", Journal of Korean Tunnelling and Underground Space Association, Vol.18, No.2, pp.129-142. https://doi.org/10.9711/KTAJ.2016.18.2.129
  13. Schanz, T., Verrmeer, P. A., and Bonnier, P. G. (1999), "The Hardening Soil Model: Formulation and Verification", Beyond 2000 in computational geotechnics, Balkema, Rotterdam, pp.1-16.
  14. Suchowerska, A. M., Merifield, R. S., Carter, J. P., and Clausen, J. (2012), "Prediction of Underground Cavity Roof Collapse Using the Hoek-Brown Failure Criterion", Computers and Geotechnics, Vol.44, pp.325-342.
  15. Tharp, T. M. (1999), "Mechanics of Upward Propagation of Covercollapse Sinkholes", Engineering Geology, Vol. 52, No.1, pp.22-33. https://doi.org/10.1016/S0013-7952(98)00051-9
  16. You, S. K., Kim, J. B., Han, J. G., Hong, G. G., Yun, J. M., and Lee, K. I. (2017), "A Study on Simulation of Cavity and Relaxation Zone Using Finite Element Method," Journal of Korean Geosynthetics Society, Vol.16, No.4, pp.67-74. https://doi.org/10.12814/JKGSS.2017.16.4.067

Cited by

  1. 포장층 두께와 교통하중 크기를 고려한 공동 발생 지반의 안정성 분석에 관한 수치해석 vol.18, pp.4, 2019, https://doi.org/10.12814/jkgss.2019.18.4.287