• Journal of the Korean GEO-environmental Society
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• v.24 no.7
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• pp.5-14
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• 2023

Recently, earthquakes have occurred frequently in worldwide. These earthquakes cause various forms of natural and physical damage. In particular, liquefaction in which the ground shows liquid-like behavior causes great damage to the structure. Accordingly, various liquefaction damage reduction methods are being studied and developed. Therefore, in this study, a method of reducing liquefaction damage in the event of an earthquake applicable to existing structures was studied using the sheet pile method. The 1-G Shaking table test was performed and the ground was constructed with Jumunjin standard sand. A two-story model structure was produced by applying the similitude law, and the input wave applied a sine wave with an acceleration level of 0.6 g and a frequency of 10 Hz. The effect of reducing structure damage according to various embedded depth ratio was analyzed. As a result of the study, the structure settlement when the ground is reinforced by applying the sheet pile method is decreased by about 71% compared to when the ground is not reinforced, and the EDR with minimum settlement is "1". In addition, as the embedded depth ratio is increased, the calculation of the pore water pressure in the ground tends to be delayed due to the sheet pile. Based on these results, the relationship with structural settlement according to the embedded depth ratio is proposed as a relational equation with the graph. The results of this study are expected to be used as basic data in developing sheet pile methods applicable to existing structures in the future.

• Journal of the Korean Geotechnical Society
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• v.36 no.12
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• pp.35-43
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• 2020

Currently, cofferdams of circular cross section are widely applied as temporary facilities for the installation of bridge foundations in river/sea bridge construction in Korea. Existing caisson, sheet pile, and cell type cofferdam are widely used, but these methods take a lot of time and cost for installation and dismantling. In the case of the existing sheet pile construction method, attention is needed to secure internal and external stability because of the damage to the sheet pile due to ground penetration and difficulty in connecting element members. In this study, penetration design of circular steel pipes using suction pressure was performed on the soft ground of the west coast, and it was confirmed that penetration construction using suction pressure was possible through field tests. It was confirmed that applying the ground analysis results using the cone penetration test (CPT) to the design rather than the standard penetration test (N value) results more similar to the field test results. In addition, it was confirmed that local failure of the inside of the cofferdam was induced when a suction pressure higher than the upper limit suction pressure was applied in the silty sand.

• Journal of the Korean Society of Hazard Mitigation
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• v.7 no.5
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• pp.179-186
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• 2007

This paper has investigated a rise of water level in upstream and downstream of bridge, which is caused by accumulation of debris in a bridge. The debris has been classified into several types in terms of size. The rise of water level which has been caused by installation and removal of sheet pile that is used to block water in a bridge has been analyzed using HEC-RAS model. According to the analysis, it has turned out that the debris has no influence on the rise of water level in ordinary water flow. In addition, sheet pile has little impact on the rise of water as well. Even though the impact of sheet file has turned out trivial in flood flow just like the ordinary water flow, it's been simulated that the maximum water level difference between upstream and downstream of bridge turned out more than 1.0meter because of debris in 80-year or more flood frequency. When the rise of water level in upstream from the cross section of the bridge was investigated based on 100-year flood frequency, besides, it has turned out that it had an influence up to 17.84km distance because of the effect of debris.

• The Journal of Engineering Geology
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• v.32 no.4
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• pp.525-534
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• 2022

This investigation used two different geophysical logging techniques to confirm the depth to which a sheet pile was driven. Depth was estimated through analysis of the movement speed and three-component movement directions of a P-wave transmitted through the ground. It was also estimated by pole-pole and pole-dipole methods using electrical data logging to measure apparent resistivity. The two methods' respective results were 9.0 m (±1.5 m) and 7.5 m. As field ground conditions will include mixtures of various materials, electrical data logging is judged to be suitable for assessing depth due to its low signal-to-noise ratio.

• Journal of the Korean Geophysical Society
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• v.8 no.2
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• pp.53-61
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• 2005

2-D and 3-D resistivity surveys were carried out at the Deok-In2 levee during the period of arid and rainy seasons to assess the waterproof effectiveness of sheet pile and routing sections and detect the location of pipings. Inverted resistivity sections clearly indicated the boundaries of sheet pile and grouting sections and the locations of pipings observed at the ground surface. It is necessary that proper survey parameters are determined considering inverted depth and resolution and contacting resistance is decreased to obtain favorable result.

• Geotechnical Engineering
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• v.36 no.5
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• pp.9-23
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• 2020

• 한국지구물리탐사학회:학술대회논문집
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• 2005.05a
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• pp.111-116
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• 2005

2-D and 3-D resistivity surveys were carried out at the Deok-In2 levee during the period of arid and rainy seasons to assess the waterproof effectiveness of sheet pile and grouting sections and detect the location of pipings. Inverted resistivity sections clearly indicated the boundaries of sheet pile and grouting sections and the locations of pipings observed at the ground surface. Besides, GPR survey was carried out to verify the rear cavity of culvert in levee which is thought to be the major cause of levee breakdown, But the quality of GPR data was very poor due to the steel reinforcements buried in the culvert. Because it is not easy to apply various geophysical surveys upon concrete structures, newly designed hydraulic response test was proposed to assess the continuity of rear cavity of culvert in this study.

• Proceedings of the Korean Information Science Society Conference
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• 2002.10c
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• pp.157-159
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• 2002

현재 생명 정보는 웹 상에서 다양한 포맷으로 배포되고 있다. 이러한 생명 정보 분석을 위한 데이터베이스나 시스템마다 이질적인 포맷을 지원하고 있기 때문에 각 시스템에서 이용되는 포맷들간의 변환이 필요하다. 이러한 생명 정보의 포맷 변환은 1대1의 파서를 구현하여 진행하고 있으며 1:1 파서의 구현에는 많은 시간과 비용이 소모된다. 따라서, 이 논문에서는 생명 정보를 XML로 표현하고 이질적인 포맷간의 매핑 정보를 데이터베이스에 저장한다. 이러한 매핑 정보를 XML의 스타일 시트로 나타내어 최종적으로 원하는 포맷으로 변환한다. 이렇게 포맷 변환에 XML기술을 이용함으로써 파서를 구현할 필요가 없이 매핑 정보를 스타일 시트로 기술하면 되기 때문에 구현이 용이하며, 원시 소스가 변경되었을 때 소스 전체를 수정할 필요가 없이 수정한 필드의 매핑 정보만 수정하고 그에 따라서 XSL을 수정하면 되기 때문에 원시 소스 변경의 영향을 많이 받지 않는다.

• Digital Contents
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• no.7 s.62
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• pp.72-75
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• 1998

오늘날 EIS는 한정된 자원을 가지고 최종 사용자에게 강건하며 동시에 유연한 상업적 데이터 마트 배급 구조를 짧은 시간안에 제공해야 한다는 어려움에 봉착해 있다. 마트 배급 구조에서 요구되는 것은 SQL에 관한 상당한 지식을 가지고 있는 전문가들로부터 항상 동일한 형식의 보고서들이나 OLAP 쿼리를 행하고자 하는 순수한 의미의 최종 사용자들에 이르는 다양한 부류의 사용자들을 지원해야 한다. 덧붙여서 이러한 구조는 ROLAP, DOLAP, 엑셀, 스프레드시트 등 모든 파일 형식상에서의 데이터 배급을 지원할 수 있을 만큼 유연해야 한다.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.895-898
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• 2008

This research paper intends to investigate and review the new technology of patent registration trend for the most recent domestic retaining wall and bridge abutment, and to apply the technology appropriately to the actual retaining wall and bridge abutment construction. Investigated new technological patents for retaining wall include pre-fabricated PC retaining wall construction method that reduces section force with prestressed PS steel bars, pre-fabricated Coupler-Tension retaining wall, clay reinforced retaining wall block for road, earth reinforced retaining wall block that induces uniform settlement, and etc. Investigated new technologies for abutment are abutment construction method that uses sheet pile, monolithic bridge with complex abutments, construction method for abutment bridge, earth reinforced abutment structure and etc.