• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.199-209
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• 2009

The movement of the caisson used to construct a wharf front can affect functional performance of the port. Sequential movement of caissons at each stage of the construction is essential in the overall design as well as the stability of the port. It is common that back-analysis using the previous measurement is performed to predict the caisson movement, while there is no intensive study on sequential movement of the caissons according to the construction stage. In the study, we analyzed the pattern of the movement of caissons as a port is constructed. To simulate the construction of the port, the finite element method (FEM) is employed. The computed result shows that the caisson moves differently at each construction stage. When the caisson is being installed, the displacement of the caisson takes place mainly in vertical direction. In next stage of filling rocks behind the caisson, the top of the caisson move toward shore, while the bottom moves toward sea, thus rotating the caisson. The maximum rotation of the caisson takes place in the stage of filling rocks behind the caisson.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.698-705
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• 2004

Application of structural load on soft ground can cause lateral movement as well as ground break due to pressing and shearing of ground. Especially, abutment supported by pile foundation can make pile deformed due to lateral movement of ground in order to have harmful effect on structure. According to the result of this study, it is required to consider disturbance of weak soil layer when using lateral movement countermeasure method by EPS construction method as a result of performing study on safety review and EPS construction method with respect to this based on site where lateral movement occurs due to backside soil filling load at bridge abutment installed on weak ground, and it is required to sufficiently consider soil reduction during design of EPS construction method due to lateral movement deformation of soft clay layer by losing ground horizontal resistance force due to plasticity of ground around pile as well as combination part damage with pile head and expansion foundation.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2010년도 춘계 학술발표회
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• pp.1473-1478
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• 2010

For the cassion type of breakwater under the condition of large wave loads, stability about lateral movement of breakwater was investigated by performing centrifuge model experiments. Prototype of breakwater was modelled by scaling down to centrifuge model and the soft ground reinforced with grouting was also reconstructed in the centrifuge model experiments. Sandy ground beneath breakwater was prepared with a soil sampled in field so that identical value of internal friction angle could be obtained. Centrifuge model experiments were carried out to reconstruct the construction sequence in field. Lateral static wave load was applied to the model caisson after the final stage of construction sequence was rebuilt and the measured lateral movement of caisson was compared with allowable value by the code to assess the stability about lateral movement of the breakwater.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2005년도 춘계 학술발표회 논문집
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• pp.1094-1101
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• 2005

The stability of embankment on the soft ground has included problems on stabilities of embanked body and soft soil, which related with vertical displacement and lateral movement of the soft ground especially. The judge methods for the potentialities of lateral movement have been used in order to stabilization assessment during and after construction of the embankment. In this study, the judge methods on the improved soft ground suggested, which compared with exist judge methods on lateral movement. It is due to recent trend using embanked structures on the soft ground most of improved.

• 농촌지도와개발
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• 제11권2호
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• pp.343-358
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• 2004

The purposes of this study were to draw out the situational problems of the community based NGO (Non Governmental Organization) movement and to suggest development strategies for NGO movement in Korea. The study was conducted through extensive review of literature and analysis of the related data. The major findings of this study were as follows; As the development of democracy and localization process were in progress, the community based NGO movement was also developing quantitatively, however not yet qualitatively. The NGO Times Net, a internet newspaper for NGOs revealed that the number of community based NGO was 3,397 as in 2004, which was 5 times larger than 597 central based or Seoul located NGOs. However, some of the problems identified were lower participation of local people, quality of the movement compare to the original purposes of the movement, and the problems in local leadership, etc. In order to overcome various problems, this study suggested some strategies for development such as enhancement of civil education, expansion of voluntary spirits, financial support for NGOs, better mutual understanding among the GOs (Government Organizations), POs(Profit Organizations) and NGOs. Self evaluation and innovative strategies will be needed for further development of NGO movement in Korea.

• 한국산학기술학회논문지
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• 제11권5호
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• pp.1799-1804
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• 2010

연약지반 위에 설치된 교대나 옹벽과 같이 성토재하중을 받는 구조물은 연약지반의 과도한 변형 때문에 지반이 수평방향으로 이동하는 측방유동 현상이 발생할 수 있고 이로 인해 많은 피해가 발생할 수 있다. 이 연구에서는 원심모형시험을 이용하여 현장에서 교대 배면부 성토시 발생할 수 있는 교대 측방유동여부를 판단하였고, 교대측방유동에 대한 대책공법으로 압성토 공법을 적용하여 공법적용 후 지반과 교대 구조물에 대한 안정성 여부를 FEM(Finite Element Method)프로그램인 MIDAS/GTS를 이용하여 검토하였다. 원심모형시험 결과 현장에서 예측되는 교대의 수평변위는 허용치(15mm)를 초과하여 발생하였으며, 대책공법으로 압성토 공법 적용할 때 교대는 측방유동에 대해 안정하다는 사실을 수치해석을 통해 알 수 있었다.

• Structural Monitoring and Maintenance
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• 제9권4호
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• pp.359-371
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• 2022

Bridges are critical to the civil engineering infrastructure network as they facilitate movement of people, the transportation of goods and services. Given the aging of bridge infrastructure, federal officials mandate visual inspections biennially to identify necessary repair actions which are time, cost, and labor-intensive. Additionally, the expansion joints of bridges are rarely monitored due to cost. However, expansion joints are critical as they absorb movement from thermal effects, loadings strains, impact, abutment settlement, and vehicle motion movement. Thus, the need to monitor bridge expansion joints efficiently, at a low cost, and wirelessly is desired. This paper addresses bridge joint monitoring needs to develop a cost-effective, real-time wireless system that can be validated in a full-scale bridge structure. To this end, a wireless expansion joint monitoring was developed using commercial-off-the-shelf (COTS) sensors. An in-service bridge was selected as a testbed to validate the performance of the developed system compared with traditional displacement sensor, LVDT, temperature and humidity sensors. The short-term monitoring campaign with the wireless sensor system with the internet protocol version 6 over the time slotted channel hopping mode of IEEE 802.15.4e (6TiSCH) network showed reliable results, providing high potential of the developed system for effective joint monitoring at a low cost.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2005년도 학술발표회(2)
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• pp.895-897
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• 2005

• 한국터널지하공간학회 논문집
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• 제17권3호
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• pp.267-281
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• 2015

본 연구에서는 흙막이벽과 같은 수직굴착과 터널과 같은 지하공간의 연속적인 굴착에 따른 지반 거동과 토압 변화를 실험적으로 연구하였다. 굴착 단계별로 벽체 거동, 토압 변화, 그리고 지표 침하의 측정이 가능한 길이 160cm, 높이 120cm의 모형 토조를 제작하였다. 실험은 균일하게 조성된 사질토 지반에서 벽체에 임의의 변위를 가하고, 토압 변화와 지표 침하를 확인하는 방식으로 수행하였다. 모형실험은 흙막이벽과 지하공간의 연속적인 시공을 모사하기 위하여 흙막이벽 굴착을 모사하는 우측벽체 10개 및 지하공간 굴착을 모사하는 하부벽체 5개를 순서대로 거동시켜 모사하였다. 실험 결과, 벽체의 주동변위로 감소된 토압이 주변 벽체로 분담되는 아칭현상이 모든 벽체에서 발생함을 확인하였다. 연속되는 시공을 모사한 실험에서 phase마다 아칭현상을 확인할 수 있으나, 하부1단 벽체의 거동 시, 우측10단 벽체는 다른 경우와 달리 토압이 50%정도만 회복됨을 보였다.

• Ecology and Resilient Infrastructure
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• 제11권1호
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• pp.1-10
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• 2024

본 연구는 하천변 대저생태공원에서 외래어종인 배스의 이동성을 파악하기 위해 시도하였다. 생태공원에 서식하는 배스 이동은 향후 낙동강 하류 영역으로 확산 가능성을 내포하고 있다는 의미이기 때문이다. 따라서 낙동강 하류 국내어종 관리를 위해서는 외래어종의 이동은 매우 중요한 자료가 될 것이다. 생태계교란 생물인 배스에 총 10개체 Radio-tag을 부착하여 총 9회에 걸쳐 안테나를 이용하여 추적하였다. 대저생태공원에서의 배스는 이동이 적은 상태로 대부분의 개체는 한 지점에서 세력권을 형성하며 서식하는 것으로 조사되었다.