Effects of Freezing a Backfill Material under Undrained Condition on a Buried Pipe

Jae-Mo Kang; Jang-Guen Lee; Hak-Seung Kim; Sang-Yoon Lee; Byung-Hyun Ryu; Nam-Jun Cho

doi:10.7843/kgs.2014.30.8.39

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2014 Vol.30, Issue 8 Preview Page

Effects of Freezing a Backfill Material under Undrained Condition on a Buried Pipe 포화 사질토 뒷채움재의 비배수 동결에 의한 매설 강관의 거동 - 실대형 모형실험 연구 -

31 August 2014. pp. 39-47

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Abstract

Frost heaving and thawing settlement cause unexpected stress around buried pipelines, which results in deformation and permanent demage. A large scale laboratory test has been performed to observe deformation, stress, and temperature of a buried pipe during atmospheric temperature changes. From the experimental results, the stress concentrated around the buried pipe is inevitable and deformation is caused by the frost heaving. Even though backfill materials are sandy soils which are normally assumed to be non frost susceptible, it is revealed that frost demage can happen due to drainage condition, the level of ground water table, and water content.

Keywords

Frost heaving

Frost susceptibility

Buried pipe

Backfill

Drainage

동절기에 지반에 매설된 상수도관은 지반의 동결 융해로 인해 과대한 지반 응력을 받게 되고, 이러한 현상이 겨울철 상수도관의 파괴 또는 변형에 많은 영향을 끼친다. 본 논문에서는 실 대형 모형실험을 통해 외부 온도 변화에 따른 매설관 주변 지반 내 온도거동과 매설관의 변위 및 응력거동을 확인하였으며, 지반이 동결됨에 따라 매설관 주변에 응력이 집중되고 동상이 발생하는 것을 확인하였다. 또한, 실험에 사용된 시료가 비동상성 시료인 사질토임에도 불구하고 함수비 조건과 배수조건에 따라 동상현상이 나타나는 것을 발견하였으며, 본 논문을 통해 매설관의 배딩(bedding)과 뒷채움재를 비동상 시료로 치환하더라도, 주변 지반의 배수상태, 지하수위, 함수비 등에 따라 동상에 대한 별도의 대책을 세워야 함을 제시하고자 하였다.

References

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2.Kang, J.M., Hong, S.S. and Kim, Y.S. (2009), A Study on Frost Heave Susceptibility of Soil Mixed with Waste Glass, JSSI&JSSE Joint Conference, Sappore, pp.74.

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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 : 30
No :8
Pages :39-47
Received Date : 2014-07-01
Revised Date : 2014-08-14
Accepted Date : 2014-08-25
DOI :https://doi.org/10.7843/kgs.2014.30.8.39

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

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