• Journal of the Korean Society of Marine Environment & Safety
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• v.13 no.4
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• pp.71-78
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• 2007

Towing vessels have carried out the important role and service in the maritime industry construction, such as port and sea bridge construction, fairway dredging and sea reclamation etc. Furthermore, tugboat takes the largest portion in number of vessel at the domestic registry and barges as big as the general merchant vessel, which are getting specialized and larger, are in operation. In spite of the increase of marine accidents under this situation, there has been no proper measure for the safe navigation of tugboat in the aspect of a nation. This paper aims to propose the measure for the safe navigation of tugboat according to the frequent marine accident of tugboat with sea bridge. Therefore, we show an example of the sailing schedule and operation checklist based on the analysis of statistics and precedent of marine accident and the investigation of the actual operation state of tugboat in the aspect of a contract of carriage and a personnel setup, which should be checked by the operator of tugboat, to pass through sea bridge safely and propose the safe traffic supporting system based on electronic chart system to improve the safe navigation of tugboat.

• Proceedings of KOSOMES biannual meeting
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• 2007.05a
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• pp.101-108
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• 2007

Tugboat has carried out the important role and service in the maritime industry construction, such as port and sea bridge construction, fairway dredging and sea reclamation etc. Furthermore, tugboat takes the largest portion in number of vessel at the domestic registry and barges as big as the general merchant vessel, which are getting specialized and larger, are in operation. In spite of the increase of marine accident under this situation, there has been no proper measure for the safe navigation of tugboat in the aspect of a nation. This paper aims to propose the measure for the safe navigation of tugboat according to the frequent marine accident of tugboat with sea bridge. Therefore, we show a example of the sailing schedule and operation checklist based on the analysis of statistics and precedent of marine accident and the investigation of the actual operation state of tugboat in the aspect of a contract of carriage and a personnel setup, which should be checked by the operator of tugboat, pass through sea bridge safely and propose the safe traffic supporting system based on electronic chart system to improve the safe navigation of tugboat.

• Journal of the Korean Society for Marine Environment & Energy
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• v.14 no.4
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• pp.239-248
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• 2011

This paper evaluated types and characteristics of development projects occurred in coastal area (Public Water) by analyzing an application status of Sea Area Utilization Conference System that effective protect and manage marine environment and ecosystem from various artificial utilization and development enforced in 2008. Also, system improvement for stable settlement and security of efficiency considering exposed problems during system enforcement were diagnosed. The number of Sea Area Utilization Conference (SAUC) performanced during the period of 2009-2010 was 3,705, which consisted of simple SAUC (87.0%), general SAUC (12.8%), and Sea Area Utilization Impact Assessment (SAUIC; 0.2%). The general SAUC was accomplished for Public Water reclamation (43.4%), seawater supply and drainage (17.5%), dredging sediment (5.5%), installation of port facilities (4.6%) and fishing harbor facilities (2.3%), and others (23.4%). Statements of Environmental Impact Assessment (EIA) were reviewed mainly for construction of port facilities (32.9%), followed by construction of industrial complex, development of tourism and leisure complex, road construction, and development of energy facilities. It would be necessary to strengthen effectiveness of the system, advertisement, and capability of conference and review agency, and to enhance confidence of marine EIA continuously, according to the increase of development projects, and diversity and enlargement of development types.

• Journal of the Korean GEO-environmental Society
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• v.18 no.2
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• pp.59-65
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• 2017

The costal reclamation construction is for making reclaimed land by dredging marine clay with seawater, and then bringing the dredged soil into the reclaimed land. During the process, the dredged soil in the reclaimed land undergoes the sedimentation-consolidation process. Among the processes, the consolidation is a very critical factor when planning reclaimed land because of its requiring time and settlement. In order to predict the requiring time and settlement, the Column test, which was suggested by Yano, has been usually used in the nation. However, the test method needs a very long time to identify the characteristic of sedimentation-consolidation of dredged soil. Therefore, in this study, in order to supplement the weakness of the Column test which needs such a long time, and in order to identify the characteristic of the sedimentation-consolidation for dredged soil in a short time, the Geo-centrifuge test was examined as an alternative method. The result considered that Geo-centrifuge test would be useful to identify the characteristic of sedimentation-consolidation for dredged soil efficiently.

• Journal of Navigation and Port Research
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• v.30 no.9
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• pp.755-762
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• 2006

When we consider to develop a new harbor, the most important factor, we think, is the lowest water depth of waterway and approaching channel for safe navigation of vessel. The existing harbors have been being dredged to meet the international trend of jumbo sized vessels by adopting the new design criteria. As the dredged materials over the expected at the design level were common and there are still lack of land based reclamation area, we have no choice to discharge the dredged materials in open sea area In this study, we analysed the behavior of discharged materials at the dumping area of offshore, which were collected from the dredging work at the waterway in Busan New Port. We measured the tidal currents and analyzed the waters of dumping site after the dumping work. These were used to evaluate the numerical models. Suspended Solids(SS) were introduced to the diffusion model. Because of the characteristic of the dumping site, the speed of initial diffusion and settle down of the discharged materials was so fast. Therefore, we believe that the dumped materials do not cause a significant impact to the marine environment.

• Journal of Korea Water Resources Association
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• v.38 no.1
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• pp.83-96
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• 2005

Three-dimensional hydrodynamic numerical simulation is carried out to investigate the effects of the coastal land reclamation on the marine hydrodynamics, environment and ecosystem. The changes of tide, tidal currents and residual currents, including tide-induced, wind driven and density driven components due to the construction of the sea dike system are simulated numerically The governing equations transformed into o-coordinates are solved by an implicit finite difference method. The numerical model is calibrated using the tide charts of 4 major tidal constituents, M$_2$, S$_2$, $K_1$ and $O_1$. The numerical solutions show that there are significant changes of residual currents, especially induced by both tidal and wind-driven currents.

• Journal of the Korean GEO-environmental Society
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• v.20 no.5
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• pp.39-46
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• 2019

Most of the soil used for reclamation is marine clay generated from dredging construction.The soft ground made of dredged clay has high water content and high compressibility, so the bearing capacity of the ground is very weak and it is difficult to enter the ground improvement equipment. Therefore, surface hardening treatment method is used to enter equipment prior to full-scale civil engineering work, and stabilizer is mainly used for cement series. Cement-based stabilizers have the advantage of improving the ground in a short period of time and have excellent economic efficiency, but they are disadvantageous in that they cause environmental problems due to leaching of heavy metals such as hexavalent chromium. In this study, environmental effects evaluation of dredged clay mixed with normal portland cement and environmentally friendly stabilizer was evaluated, and uniaxial compressive strength test and indoor model test were conducted to confirm the bearing capacity characteristics of the solidified layer.

• Journal of the Korean Society for Marine Environment & Energy
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• v.16 no.4
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• pp.290-298
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• 2013

A Saemangeum Development Project, which is a national project in South Korea, has started with the objective of developing the reclaimed area mainly agricultural land use since the mid'80s. To develop a model of the global eco-reclamation, constructions of the eco-friendly counter facilities such as sluice gates and inner dikes, as well as environmental preservation measures for an estuary reservoir, have been carried out. However, reasonable measures of the water quality management for the Saemangeum area are required. Thus, the purpose of this study is to rigorously analyze and quantitatively evaluate the environmental problems due to the water level management associated with inner dike constructions. To achieve these objectives, the affecting factors on determination of water level management are described and a series of calibrated transient-state numerical simulations was performed to demonstrate the salinity distribution difference in the estuary before and after the construction of inner dikes. The overall salinity reduced about 2~5 psu, and the seawater intrusion was weakened by a well-regulated waterway after construction of the inner dikes compared to before construction of them.

• Journal of the Korean GEO-environmental Society
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• v.11 no.11
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• pp.37-45
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• 2010

In this study, the value of numerical analysis was compared to the measured value of horizontal displacement during construction. And also, the value was reviewed by comparing with numbers calculated by SUNEX program and EXCAV program. When comparing to suggested values of the maximum horizontal displacement in clayey layer, the displacement caused by the IPS system is larger than one by the Strut girder type system. When comparing the result of SUNEX program to that of EXCAV program, the SUNEX program interprets larger value. It could be concluded the result of SUNEX program is closer to the suggested value, 0.5%H, in clayey layer. The result also shows that the internal friction angle(${\Phi}$) is the key factor of developing horizontal displacement rather than type of supporting systems or materials. That means small horizontal displacement occurs in sandy layer having large value of the internal friction angle, whereas vice versa in clayey layer having small value of the internal friction angle. Therefore, the result of EXCAV program is larger in sandy layer and vice versa in clayey layer. When comparing the measured result during construction to the value of 0.5%H, the measured result is 1.4 times greater than the value of 0.5%H. In contrast, the result of SUNEX program is only 78.1% of the value of 0.5%H and the one of EXCAV program is just 18.1% of that. This result shows the calculated value by SUNEX or EXCAV program is smaller than the observed value by measuring during construction. In result, more careful attention is needed to determine the behavior of the ground. To better analyze the behavior of the ground, more precise finite element method is required.

• Journal of the Korean Association of Geographic Information Studies
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• v.14 no.4
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• pp.128-136
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• 2011

To monitor and predict the change of coastal environment according to the construction of Saemangeum sea dyke and the development of land reclamation, we have done real-time and periodic ocean observation and numerical simulation since 2002. Saemangeum coastal environmental data can be largely classified to marine meteorology, ocean physics and circulation, water quality, marine geology and marine ecosystem and each part of data has been generated continuously and accumulated over about 10 years. The collected coastal environmental data are huge amounts of heterogeneous dataset and have some characteristics of multi-dimension, multivariate and spatio-temporal distribution. Thus the implementation of information system possible to data collection, processing, management and service is necessary. In this study, through the implementation of Saemangeum coastal environmental information system using geographic information system, it enables the integral data collection and management and the data querying and analysis of enormous and high-complexity data through the design of intuitive and effective web user interface and scientific data visualization using statistical graphs and thematic cartography. Furthermore, through the quantitative analysis of trend changed over long-term by the geo-spatial analysis with geo- processing, it's being used as a tool for provide a scientific basis for sustainable development and decision support in Saemangeum coast. Moreover, for the effective web-based information service, multi-level map cache, multi-layer architecture and geospatial database were implemented together.