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

Seung-Kyong You; HeeChul Ahn; Young-Ho Kim; Jung-Geun Han; Gigwon Hong; Jeong-Jun Park

doi:10.7843/kgs.2019.35.1.43

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2019 Vol.35, Issue 1 Preview Page

Research Article

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

31 January 2019. pp. 43-53

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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.

Keywords

Cavity

Relaxation zone

Forced displacement

Shear stress reduction ratio

Finite element analysis

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 주변 지반의 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.

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Information

Publisher :The Korean Geotechnical Society
Publisher(Ko) :한국지반공학회
Journal Title :Journal of the Korean Geotechnical Society
Journal Title(Ko) :한국지반공학회 논문집
Volume : 35
No :1
Pages :43-53
Received Date : 2018-12-17
Revised Date : 2019-01-18
Accepted Date : 2019-01-22
DOI :https://doi.org/10.7843/kgs.2019.35.1.43

Journal of the Korean Geotechnical Society ISSN:1229-2427(Print) 2288-646X(Online) 한국지반공학회 논문집

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