Journal of the Korean Geotechnical Society (한국지반공학회논문집)

Korean Geotechnical Society (한국지반공학회)
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A Study for Influence Range of Ground Surface due to Sewer Fracture in Various Relative Density of Sand by Laboratory Model Test

실내모형시험을 통한 상대밀도가 다양한 사질토 지반에서의 하수도관 파손에 따른 지표침하의 영향범위에 관한 연구

  • Oh, Dong-Wook (Dept. of Civil Engrg., Seoul National Univ. of Science & Technology) ;
  • Ahn, Ho-Yeon (Dept. of Civil Engrg., Seoul National Univ. of Science & Technology) ;
  • Lee, Yong-Joo (Dept. of Civil Engrg., Seoul National Univ. of Science & Technology)
  • 오동욱 (서울과학기술대학교 건설시스템공학과) ;
  • 안호연 (서울과학기술대학교 건설시스템공학과) ;
  • 이용주 (서울과학기술대학교 건설시스템공학과)
  • Received : 2015.12.14
  • Accepted : 2016.02.25
  • Published : 2016.02.29
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Abstract

It is well known that water leakage from decrepit sewer pipe mainly causes frequent occurrence of ground subsidence in urban area. Thus, laboratory model tests were carried out to investigate ground behaviour according to location of sewer fracture and various relative densities of surrounding soil. The portion of fractured pipe was assumed to be 20% compared to the circumference of pipe, and to be positioned at the top and bottom of the pipe. Ground conditions were made as loose sand ($D_r=30%$) and dense sand ($D_r=70%$). In addition, comparison and analysis with results of model tests were carried out by Finite Element analysis. As a result, not only water leakage from the bottom of pipe (scenario 2) caused greater ground behaviour than leakage from the top of pipe (scenario 1), but also much greater surface settlement occurred when the ground condition is loose.

도심지 지반함몰 현상의 대부분이 노후된 하수관에 의해 발생한다는 것은 이미 잘 알려진 사실이다. 따라서 관 파손의 위치와 주변 지반의 상대밀도가 지반의 거동에 미치는 영향을 알아보기 위해 실내모형시험을 수행하였다. 관 파손은 관 둘레에 대해 20% 파손된 것으로 가정하여 관 상부에 파손이 발생한 경우와 하부에 발생한 경우로 고려하였다. 느슨한 지반과 조밀한 지반을 상대밀도 30%, 70%로 조성하여 관 파손의 위치에 따른 지반 거동을 측정하였을 뿐만 아니라, 유한요소해석을 이용하여 실내모형시험 결과와 비교 분석하였다. 관 하부가 파손되어 누수가 발생되는 것이 상부가 파손되는 것보다 더 큰 지반 거동을 유발하는 것으로 나타났을 뿐만 아니라, 느슨한 지반에서 더 큰 지표침하량이 발생하는 것을 알 수 있었다.

Keywords

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