• 수산해양기술연구
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• 제43권3호
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• pp.212-221
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• 2007

This paper describes on the evaluation and management of work process in suction hopper dredger and grab bucket dredger as an application of a PC-based ECDIS system. The dynamic tracking of dredging bucket and the data logging of grab dredging information were performed by using the grab dredging vessel "Kunwoong G-18". The position and route tracking of the dredger moving toward the ocean dumping site of dredged material was performed by using the hopper dredging vessel "Samyang-7". The evaluation of wok process in the dredging field, for grab dredger, was continuously carried out on January to May, 2006, in Incheon Hang and for hopper dredger, on July to December, 2003, in Busan Hang, Korea. The dredging information, such as dredger's position, heading, dredging depth and route track which was individually time stamped during the dredging operation, was automatically processed in real-time on the ECDIS and displayed simultaneously on the S-57 ENC chart. From these results, we conclude that the ECDIS system can be applied as a tool in order to manage the work process during the dredging operation, and also in order to generate the factual record of the dredging activities that is sufficient for dredging inspector to accurately evaluate the contract performance even in the absence of a full-time onboard inspector.

• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2000년도 추계학술대회논문집
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• pp.95-107
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• 2000

The primary purpose of dredging work is to maintain navigational readiness and to increase environmental amenity, so that the dredging project which is composed of excavating, removing, transporting, storing and disposing dredged material must be carefully managed to insure that dredging works are completed in a cost-effective and environmentally safe manner. The most important point in dumping operations is an estimating and reducing the impacts of discharges at the dumping area. One of the most effective method for the reduction of ecological impacts at dumping area is using the schematic process composed of the sophisticated plan, precise work and predicting/reducing the impacts based on the numerical model and field observation. In this study, the numerical model is used to predict the near-field spatial fate and begavior of effluent discharged from Confined Dumping Facility(CDF) located near coastal area. To to this purpose, reappearing of tidal current was preceded. The model is then applied to Mokpo harbor, where capital dredging and maintenance dredging are conducted simultaneously and the CDF is under construction;. In the series of model case study, we found that the near-field behavior of effluent discharged from CDF was governed by the receiving water condition, outfall geometry, characteristics of efflent and CDF operating conditions.

• 한국항만학회지
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• 제14권4호
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• pp.429-439
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• 2000

The primary purpose of dredging work is to maintain navigational readiness and to increase environmental amenity. Therefore the dredging project, which is composed of excavating, removing, transporting and storing or dumping dredged material, must be carefully managed to insure that dredging works are completed in a cost-effective and environmentally safe method. The most important point in dumping operations is evaluating and decreasing the impacts of dumping works at the dumping area. One of the most effective method for this purpose is using the schematic process composed of the sophisticate plan, precise work and predicting/reducing the impacts based on an numerical model being closely linked with field observation. In this study, a numerical model is used to predict the spatial transport and fate of the effluent discharged from the confined dumping facility(CDF) located at a coastal area. To achive this purpose, numerical models were used for reappearing the tidal current of concerned area. These models were then applied to Mokpo harbpr where capital dredging and maintenance dredging are being conducted simultaneously and the CDF is under construction. In series of model case study, we found that the effluent discharged from CDF was governed by the receiving water condition and outfall geometry, so that limit of near-field was 14∼500 meter down stream and 4∼150 meter in transverse direction. dilution ranged from 1.1 to 8.2 on the cases. Long-term diffusion characteristics was governed by the dilution rate during near-field behavior, ambient conditions and CDF operation modes.

• 한국항만학회지
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• 제11권2호
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• pp.203-214
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• 1997

Hydraulic dredgers(Hopper dredger) are the most important piece of equipment in the entire harbor engineering field, and most suitable for the removal of sand and weakly consloidated sediment such as silt. In maintenance dredging, specially confined harbor or congested passage area, Hopper dredger is user most popularly because less obstruction and danger to navigation than other mostly stationary dredgers. Investigation of the physical behave of dredged material disposal in coastal water from the Hopper dredger includes estimations of pattern as well as thickness of material on the bottom. Calculation based on vertical settling and horizontal advection of single particles ignore the effects of bulk properties of the disposed marterial, vertical and horizontal diffusion. and material dilution due to the entrainment of ambient water during descent. This paper focuses on the analysis of dredging and dumping characteristics and the spatial and temporal changes in the dumping fields for the water column and bottom at a hypothetically confined coastal water. This model accounts the behavior of material after release from the hopper dredger. It is shown that the model describes the qualitative feature of prototype dumping process and its response.

• 한국지반공학회지:지반
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• 제10권1호
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• pp.71-82
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• 1994

준설매립지의 현장계측결과에 의하면 실제의 자중압밀 침하량은 실내시험결과를 근거로한 설계치보다 작게 평가되고 있다. 이러한 원인중의 하나를 본 연구에서는 준설재료의 퇴적시 압축성의 저감에 의한 것이며 더욱이 이러한 시간효과는 펌프준설매립지와 같이 저응력범위의 압밀특성에서는 고려되고 있지 않는 실정이다. 본 논문에서는 준설점성토의 압축성에 대한 시간효과를 파악하기 위하여 퇴적된 공시체에 침투력을 작용시켜 일련의 침투압밀시험을 수행하였다. 또한 본 연구에서와 같이 초기함수비가 큰 경우에 발생하는 압밀해의 불안정성을 극복하기 위하여 예측자-수정자법을 이용한 유한차분에 석기법을 제시하였고 실험결과와 비교하여 좋은 결과를 얻었다. 최종적으로 준설점성토의 압축성은 자중압밀시간에 의존되고 있음이 관찰되었다.

• 한국연안방재학회지
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• 제5권4호
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• pp.173-182
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• 2018

As the research about increasing the efficiency of dredging soil transport, the technology, which reduce the friction between pipe wall and fluid in the pipe and disturbed generating pipe blockage, has been developed. So for the purpose of applying this technology to real construction site, main test has been tried at the real scale test in field. As a test result, this paper will show 30% flow efficiency increasing by permitted electro magnetic force to the pipe. And test result was evaluated as a ultra sonic velocity profiler. To propose the design technique and the execution manual of the high efficiency dredging material transport technic, this research have confirmed flow status changing depending on a soil material kind under electro-magnetic field and analyze the effect of electro-magnetic field which affects to each dredged soil material transportation. For achieving this research, EMF(Electro-Magnetic Field) generator is installed on the dredger(20,000HP) and through monitored flow status, dredging soil flow rate and sampled material specification is confirmed. Also dredger operating condition is measured and dredger power for soil transportation, hydraulic gradient and flow rate are compared, as transportation efficiency is calculated by this parameter, it is possible to check transportation efficiency improvement depending on each dredged soil material under electro-magnetic field. To verify the technique of dredged soil transfer using electromagnetic field, which is the core technique of the high efficiency dredged soil transfer, and the technique of expert system for pipeline transfer and the flow state. This could lead to a verification of transfer efficiency according to the characteristics of the dredged soil (sand, clay, silt) and the transfer distance (5km, 10km, 15km), which is planned to be used for a technology development of pump power reduction and long-distance transfer applying the high efficiency dredged soil transfer technology.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2002년도 봄 학술발표회 논문집
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• pp.549-556
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• 2002

Geotextile tubes hydraulically or mechanically filled with dredged materials have been applied in hydraulic and coastal engineering in recent years(shore protection structure, detached breakwater, groins and jetty). It can also be used to isolate contaminated material from harbor, detention basin dredging, and to use this unit as dikes for reclamation work. Recently, new preliminary design criteria supported by model and prototype tests, and some stability analysis calculations have been studied. The stability analysis of geotextile tube is composed geotechnical and hydrodynamic analysis. The stability check points are sliding failure, overturning, bearing capacity failure against the wave attack. In this paper presented the construction procedure and in-situ measurement(properties of filling material, effective height variation, stress variation at geotextile tube bottom) of geotextile tube at Young-Jin Bay and stability analysis by theoretical method and hydraulic model tests

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 1998년도 준설 및 환경매립에 관한 학술세미나
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• pp.1-29
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• 1998

• 지반과기술
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• 제7권2호
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• pp.23-35
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• 2010

• 한국지반환경공학회 논문집
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• 제23권5호
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• pp.15-24
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• 2022

준설 매립지반의 경우 공학적, 물리적 조건이 열악하여 매립현장에서 이를 개량하기 위한 시간과 비용이 많이 든다. 또한 국내 실정에 적합한 관중혼합 이송처리 공법의 적용사례가 없고 공법 적용성 및 효과에 관하여 불확실할 뿐 아니라 실제 현장과 실내실험 간의 차이가 발생할 수 있다. 이러한 문제점을 해결하기 위해 개질재(표준사+입도조절재)가 혼합된 준설토를 대상으로 실내 특성실험을 통해 개질재의 적정한 입도분포 및 함수비 범위를 결정하였다. 그 결과 단계투기 시 침강압밀계수가 증가하고 분리침강에 대한 개선효과가 있는 것으로 확인되었다. 실험결과 회귀분석을 통해 개질 처리토의 함수비에 따른 비배수전단강도를 도출하고, 이를 활용하여 배합비를 결정할 수 있는 상관식을 제시하였다.