• Journal of the Korean Society of Hazard Mitigation
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• v.8 no.1
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• pp.47-55
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• 2008

Recently, it has been reported that buried pipes' crack is concentrated on curved parts. In this study, 3D-Finite element analysis is performed for Analytical Evaluation on the Structural Safety of Horizontally Curved Parts of Buried Pipe. The constructed pipe cracked in curved parts of pipe is analyzed and all kinds of loads affected to buried pipes are considered. Displacement, stresses and buckling analysis are performed. The stress analysis shows that stress in curved parts is larger than stresses in straight parts and exceeds allowable stress in some parts. So, stress analysis on curved parts is needed for safety for buried pipe.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.12 no.3
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• pp.1439-1443
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• 2011

A theoretical study on the ground water flow adjacent to buried pipe was conducted. Incompressible and irrotational flow were considered in analytical study. Ground water flow were defined by complex potentials. Firstly, uniform flow without buried pipe was analysed and then the effect of buried pipe was considered by superposition via circle theorem. Although two kinds of flow can be added by linearity of complex potentials, investigation of the singularities of the complex potentials should be done in advance. Finally, ground water flow past a buried pipe was analysed via complex potentials and net force exerted on the buried pipe by the ground water flowing past with circulation was derived.

• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.49-58
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• 2003

Underground flexible pipes for electric cables are subject to external loads and surrounding soil pressure. Particularly, strain of flexible pipes is of great concern in terms of safety and maintenance for electric cables. In this paper, stress and strain of flexible pipes with various installation depth are compared using traditional formula, FEM analysis, model soil box test and field test. from the findings of various analyses, considering the strain criteria-maximum 3.5%, it is suggested that flexible pipes can be buried at the depth of 80cm without additional soil improvement.

• Journal of the Korean Geotechnical Society
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• v.18 no.4
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• pp.65-73
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• 2002

Underground flexible pipes for electric cables are subject to external loads and surrounding soil pressure. Particularly, strain of flexible pipes is of great concern in terms of safety and maintenance for electric cables. In this paper, stress and strain of flexible pipes with various depth are compared using traditional formula, FEM analysis and model soil box test. The results show that theoretical values are more conservative in strain in comparison with model soil box test and FEM analysis. Considering the strain criteria - maximum 3.5%, flexible pipes can be buried at the depth of 40cm without additional soil improvement. From the result of this study, deformation formula compatible with the field condition was proposed.

• Journal of the Korean Institute of Gas
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• v.5 no.3 s.15
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• pp.9-14
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• 2001

현재까지 국내에서는 지진에 대한 위험성을 인식하고 건축물 및 교량등에 대한 내진설계 연구가 활발하게 진행중이지만 지중에 매설된 관에 관한 연구는 미약한 실정이다. 지중매설관 중 가스관의 파손은 주변의 환경과 인명에 심각한 영향을 줄 수도 있으므로 인명보호와 타시설의 보호를 위해서는 가스관의 내진설계에 대한 검토가 요구된다. 본 연구에서는 지중매설관중 가스관의 내진성을 검토하기 위해서 가스관의 파손을 일으키는 원인 중에 하나인 액상화에 의한 영구지반변형에 대하여 매설관의 거동을 분석하였다. 이를 위하여 외국의 사례를 분석하고 우리나라 가스관에 대한 해석을 수행하여 지진에 대한 안정성을 검토하였다.

• Journal of the Korean Society for Advanced Composite Structures
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• v.2 no.2
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• pp.26-33
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• 2011

Recently, the use of buried glass fiber reinforced plastic (GRP) pipes is widespread and ever increasing trend in the industry. GRP pipes are attractive for use in harsh environments, such as for the collection and transmission of liquids which are abrasive and/or corrosive. The structural behavior of a GRP pipes buried under the ground is different from that of a rigid one made of concrete or clay, for example. A GRP pipe buried under the ground is deflected circumferentially by several percent and the stresses in the pipe are mainly compressive stresses. A GRP pipes has been introduced by a number of manufacturers for selection and used by underground pipeline designers. In all cases, the modified Spangler's equation is recommended by these manufacturers for predicting the ring deflection of these pipes under dead and live loads. In this paper, the ring deflection of buried GRP pipe is evaluated and discussed based on the result of analytical investigation.

• Journal of the Korean Geotechnical Society
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• v.19 no.5
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• pp.79-87
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• 2003

Underground flexible pipes for electric cables are subject to external loads and surrounding soil pressure. Particularly, strain of flexible pipes is of great concern in terms of safety and maintenance of electric cables. In this paper, stress and strain of flexible pipes with two types of installation gap, ie, l0cm and naught, were compared to investigate the structural integrity of pipes from actual field test. The effect of degree of compaction and burial depth were also investigated to simulate the variety of construction situation. The results of the field test show that the strain criteria were satisfied under the burial depths of 80cm, 100cm and 120cm regardless of installation gap.

• Journal of the Korean Geosynthetics Society
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• v.13 no.1
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• pp.33-40
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• 2014

In general, pipes buried underground can be classified into either rigid or flexible pipe. Glass fiber reinforced thermosetting polymer plastic (GFRP) pipe can be considered as one of typical flexible pipes for which the soil-pipe structure interaction must be taked into account in the design. In this paper, we present the result of an investigation pertaining to the short-term and long-term behavior of buried GFRP pipe. The mechanical properties of the GFRP pipe produced in the domestic manufacturer are determined and the results are reported in this paper. In addition, Ring deflection is measured by the field tests and the finite element analysis. Also, the extrapolation using these techniques typically extends the trend from data gathered over a period of approximately 5,232 hours, to a prediction of the property at 50 years, which is the typical maximum extrapolation time. Therefore, it was investigated that the long-term ring deflection of GFRP pipe estimated by methods for Monod-type.

• Journal of Animal Environmental Science
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• v.11 no.1
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• pp.25-34
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• 2005

The study aimed to develop a tractor drawn animal slurry manure sub-soil injector for arable land and thus, can reduce the waste management cost through effective treatment and utilization of animal slurry manure. The application of animal slurry manure to agricultural land will probably be one of the most effective ways to enrich the soil with vital nutrients. However, some existing slurry manure spenders are not suitable in the field because of their adverse effects to the environment. Based on this premise, a prototype was designed and assembled using 5 sub-soiling standards attached to the sin injector device. The traction force of the Prototype measured in the depth of 10 cm and 15 cm from the ground surface of a paddy field was 1,062 kgf and 1,214 kgf, respectively. A unique feature of the machine was that there was an equal volume of slurry manure flowing from each delivery pipe and regulated by a pressurized container that was likewise synchronized with the speed of the tractor The sub-soiling manure injection system can mitigate or reduce the harmful emission of obnoxious gases and malodor during the injection operation.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.244-246
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• 2023

아파트 신축공사 흙막이 가시설 현장에 근접 매설된 상수관의 누수 및 파열 사고로 인접 건물이 공사현장 방향으로 58~188mm 기울어졌으며, 지중수평경사계 계측결과 21.07.20일 22.64mm가 21.10.18.일 101.46mm로 급격하게 78.82mm의 큰 수평 변위가 발생되었으며, 이로 인해 흙막이 가시설의 사보강재가 변형되고 토류판 일부가 파손되었다.