Understanding of Subsurface Cavity Mechanism due to the Deterioration of Buried Pipe

Dae-Young Lee; Nam-Kak Cho

doi:10.7843/kgs.2016.32.12.33

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2016 Vol.32, Issue 12 Preview Page Next Page

Understanding of Subsurface Cavity Mechanism due to the Deterioration of Buried Pipe 노후 매립관로로 인한 지하 공동발생 메카니즘 고찰

31 December 2016. pp. 33-43

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Abstract

In order to analyze ground relaxation and cavity formation mechanism due to deteriorated sewer pipe, field test was carried out and a numerical assessments were compared with the field test results. An artificial underground cavity was intended using the ice block overlaying the buried pipe and confirmed that the cavity and relaxation of the surrounding ground were gradually formed as the ice block starts to melt down. Such mechanism was highly suspected to be involved with soil particle interlocking as a soil compaction was a typical process for the buried pipes. In exploring such mechanism numerically, commercially available DEM (Discrete Element Method) code PFC2D was used and the interlocking induced cavern behaviors were successfully simulated and compared with field test results by utilizing the clump logic imbedded in PFC code.

Keywords

Sinkhole

Ice cavity

DEM

PFC

Flowable Fill

Cavity formation mechanism

Sewer pipe

노후관로로 인한 지반내 공동형성과 지반이완 메카니즘을 분석하기 위해 현장시험을 수행하였으며 수치해석을 수행하여 현장시험과 비교하였다. 현장시험은 지반내 인위적인 공동을 만들기 위해 얼음을 이용하였으며, 시간경과에 따른 얼음의 융해로 인해 공동형성과 주변지반의 이완을 확인할 수 있었다. 다짐된 토사의 interlocking에 의한 이완 및 공동형성 거동을 고려하기 위하여개별요소법에 근거한 수치해석 프로그램인 PFC 2D를 이용하였다. PFC의 클럼프(clump) 요소를 도입하여 불규칙 형상의 입자를 모사하였으며, 이를 통해 얻은 공동형성과 지반이완 특성을 현장시험결과와 비교함으로써 지반내 공동형성 및 거동특성을 파악하였다.

References

References

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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 : 32
No :12
Pages :33-43
Received Date : 2016-07-18
Revised Date : 2016-09-20
Accepted Date : 2016-10-25
DOI :https://doi.org/10.7843/kgs.2016.32.12.33

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

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