• Journal of Korean Society of Coastal and Ocean Engineers
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• v.25 no.3
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• pp.128-137
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• 2013

Due to the global warming and air pollution, interest in renewable energies has increased in recent years. In particular, the crisis of the depletion of fossil energy resources in the near future has accelerated the renewable energy technologies. Among the renewable energy resources, oceans covering almost three-fourths of earth's surface have an enormous amount of energy. For this reason, various approaches have been made to harness the tremendous energy potential. In order to achieve two purposes: to improve harbor water quality and to use wave energy, this study proposed a sea water exchange structure applying an Oscillating Water Column (OWC) wave generation system that utilizes the air flow velocity induced by the vertical motion of water column in the air chamber as a driving force of turbine. In particular, the airflow velocity in the air chamber was estimated from the time variations of water surface profile computed by using 3D-NIT model based on the 3-dimensional irregular numerical wave tank. The relationship of the frequency spectrums between the computed airflow velocities and the incident waves was analyzed. This study also discussed the characteristics of frequency spectrums in the air chamber according to the presence of the structure, wave deformations by the structure, and the power of the water and air flows were also investigated. It is found that the phase difference exists in the time series data of water level fluctuations and air flow in the air chamber and the air flow power is superior to the fluid flow power.

• Journal of the Korean GEO-environmental Society
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• v.7 no.4
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• pp.53-62
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• 2006

Recently, the lateral displacement of the passive piles which are installed under the revetment on the soft ground is very important during the land reclamation work along the coastal line. The revetment on the soft clay develops the lateral displacement of ground when the revetment loading exceeds a certain limit. The lateral displacement of ground causes an excessive deformation of underground structure itself and develops lateral earth pressure against the pile foundation. The subject of study is to investigate the lateral displacement of pile foundation during the construction of container terminal at the ${\bigcirc}{\bigcirc}{\bigcirc}{\bigcirc}$ port in Incheon. The displacement of pile and the vertical settlement were measured in the field and finite element method(FEM) analysis for each construction sequence was performed using AFFIMEX(Ver 3.4). From the comparison of the results from field measurement and the finite element analysis, the settlement of the reventment has already occurred at the time of field measurements. Since then, the noticeable lateral displacement of piles and settlement were occurred during the filling of dredged soil inside the revetment dredging and reclaiming work. After completing filling, the lateral displacement and field settlement were reduced remarkably. Generally, the results from the finite element analysis show larger than those from the measurement.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.11
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• pp.510-518
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• 2020

With the promotion of digitalization in the construction industry, BIM has become an indispensable technology. On the other hand, it has not been actively utilized in practice because of the difficulty of BIM modeling. The reason is that 3D modeling is less productive not only because of the difficulty of learning BIM software but also the modeling work is done manually. Therefore, this study proposes a method and system that can improve the productivity of BIM-based modeling. For this reason, in the study, a slit caisson, which is a typical structure of a port, was selected as a development target, and various parameters were derived through interviews with experts so that it could be used in practice. This study presents a UI construction plan that considers user convenience for efficient management and operation of diverse and complex parameters. Based on this, this study used visual programming and Excel VBA to develop a BIM-based design automation system for slit caissons. The developed system can use many parameters to quickly develop slit caisson models suitable for various design conditions that can contribute to BIM-based modeling and productivity improvement.

• 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 the Korean Geotechical Society Conference
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• 2009.09a
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• pp.133-144
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• 2009

Incheon Bridge, 18.4 km long sea-crossing bridge, will be opened to the traffic in October 2009 and this will be the new landmark of the gearing up north-east Asia as well as the largest & longest bridge of Korea. Incheon Bridge is the integrated set of several special featured bridges including a magnificent cable-stayed girder bridge which has a main span of 800 m width to cross the navigation channel in and out of the Port of Incheon. Incheon Bridge is making an epoch of long-span bridge designs thanks to the fully application of the AASHTO LRFD (load & resistance factor design) to both the superstructures and the substructures. A state-of-the-art of the geotechnologies which were applied to the Incheon Bridge construction project is introduced. The most Large-diameter drilled shafts were penetrated into the bedrock to support the colossal superstructures. The bearing capacity and deformational characteristics of the foundations were verified through the world's largest static pile load test. 8 full-scale pilot piles were tested in both offshore site and onshore area prior to the commencement of constructions. Compressible load beyond 30,000 tonf pressed a single 3 m diameter foundation pile by means of bi-directional loading method including the Osterberg cell techniques. Detailed site investigation to characterize the subsurface properties had been carried out. Geotextile tubes, tied sheet pile walls, and trestles were utilized to overcome the very large tidal difference between ebb and flow at the foreshore site. 44 circular-cell type dolphins surround the piers near the navigation channel to protect the bridge against the collision with aberrant vessels. Each dolphin structure consists of the flat sheet piled wall and infilled aggregates to absorb the collision impact. Geo-centrifugal tests were performed to evaluate the behavior of the dolphin in the seabed and to verify the numerical model for the design. Rip-rap embankments on the seabed are expected to prevent the scouring of the foundation. Prefabricated vertical drains, sand compaction piles, deep cement mixings, horizontal natural-fiber drains, and other subsidiary methods were used to improve the soft ground for the site of abutments, toll plazas, and access roads. Light-weight backfill using EPS blocks helps to reduce the earth pressure behind the abutment on the soft ground. Some kinds of reinforced earth like as MSE using geosynthetics were utilized for the ring wall of the abutment. Soil steel bridges made of corrugated steel plates and engineered backfills were constructed for the open-cut tunnel and the culvert. Diverse experiences of advanced designs and constructions from the Incheon Bridge project have been propagated by relevant engineers and it is strongly expected that significant achievements in geotechnical engineering through this project will contribute to the national development of the longspan bridge technologies remarkably.

• 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 Geotechnical Society
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• v.38 no.4
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• pp.33-45
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• 2022

A series of model tests were performed in this study to demonstrate the clogging mechanism created during the installation of a compaction pile to improve soft ground. The application of an air-jet to extrude sand or aggregates from a casing during the installation of a compaction pile imposes a remarkably high-pressure difference between the composite soil layers of clay and sand (or aggregates), resulting in severe clogging. Therefore, a one-dimensional testing system was developed to simulate composite soil layers consisting of clay and sand (or aggregates) and to apply a high-pressure differential at both boundaries, thus replicating the extrusion process used in compaction pile installation. Herein, the performance of two construction materials for compaction piles of crushed stone and grading-controlled aggregates was compared. A series of one-dimensional model tests were performed under multiple pressure settings, with clogging depth and permeability measured in each case. Results indicate that, blinding clogging mechanisms and blocking defined by previous studies were observed for crushed stone, and a new mechanism of "infiltration" was revealed and defined. Whereas, the controlled aggregates performed excellently against clogging because only blinding was observed.

• Journal of the Korean Geosynthetics Society
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• v.22 no.1
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• pp.87-96
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• 2023

There are a lot of difference between the surface settlement and the differential settlement measured at the Busan New Port, where the dredged and reclaimed clay layer exists and below the clay is originally thickly distributed. To find the cause and solution of this, the actual conditions of each differential settlement used for the soft ground improvement, characteristics, installation method, measurement frequency, measurement data management, and data analysis of each type were considered. In the deep soft ground improvement work where large deformation occurs, the bending deformation of the screw-type differential settlement gauge is less than that of other types of measuring instruments, so there is less risk of loss, and the reliability of data is relatively high as the instruments are installed by drilling for each stratum. Since the greater the amount of high-precision settlement measurement data, the higher the settlement analysis precision. It is necessary to manage with higher criteria than the measurement frequency suggested in the standard specification. For the data management of the differential settlement gauge, it is desirable to create graphs of the settlement and embankment height of the relevant section over time, such as surface, differential, and settlement of pore water pressure gauge for each point. In the case of multi-layered ground with different compression characteristics, it is more appropriate to perform settlement analysis by calculating the consolidation characteristics of each stratum using a differential settlement data.

• The Journal of the Korea Contents Association
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• v.22 no.8
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• pp.126-139
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• 2022

This study aims to present the criteria of location selection and contents composition of Sewol ferry memorial space from the perspective of placeness and dark tourism, one of the main concepts of cultural tourism theory, and to draw academic concepts and implications related to it. First, the location selection of Sewol ferry memorial space was proposed by applying the concept of placeness to each important location, and the direction of the contents composition was presented based on the contents components such as characters, stories, places and dark tourism composition directions. As a result, when the Sewol ferry memorial space is designed in use of systemizing the narrative structure of the storytelling method and implementing it specifically, it is suggested that it is possible to construct a Sewol ferry memorial space by distributing and course-making based on the narrative structure rather than focusing on the location selection of a specific place. In addition, it was argued that the contents composition criteria should be more complex and systematically established and applied considering the connection between placeness and dark tourism when the Sewol ferry memorial space is constructed in various sites like 416 life safety parks and Mokpo New Port. This study, which aims to answer research questions related to major issues based on the perspective of placeness and dark tourism on the Sewol ferry memorial space, is expected to be used as a reference for the construction of the memorial space in the future.

• Journal of the Korean Society of Marine Environment & Safety
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• v.16 no.3
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• pp.275-285
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• 2010

Present state of nationwide marine facilities reported to 12 regional maritime affairs and port offices of MLTM in Korea for two years 2008 and 2009 was analyzed based on region and type of facilities, and national management plan was proposed in this study. As of the end of 2009, 8 types of marine facilities were reported to Yeosu regional maritime affairs and port office, while only 3 types of facilities were reported to Pohang, Daesan and Jeju regional offices, respectively. Oil and noxious liquid substances storage facilities belonged in the type of facility which was reported to all of 12 regional offices, and ranged from 11 facilities reported to Pyeongtaek regional office to the respective 38 facilities to Yeosu and Masan regional offices. In pollutants storage facilities, 4 facilities were reported to Masan regional office, 2 facilities to Donghae and Mokpo regional offices, respectively, 1 facility to Yeosu, Gunsan and Pyeongtaek regional offices, respectively, and none of facilities to the other regional offices. Ship construction, repair and scrap facilities belonged in the type of facility which was reported to all of 12 regional offices, and 45% of the facilities were concentrated in Southeastern Sea of Korea centering around Busan and Masan. In cargo handling facilities, 3 facilities were reported to Busan and Masan regional offices, respectively, 1 facility to Daesan regional office, and none of facilities to the other regional offices. In wastes storage facilities, 5 facilities were reported to Ulsan regional office, 4 facilities to Gunsan regional office, 2 facilities to Incheon regional office, 1 facility to Yeosu regional office, and none of facilities to the other regional offices. 65% of nationwide water intake and drainage facilities were concentrated in the areas of Pohang and Mokpo, and 78% of nationwide fishing spots at play were concentrated in the area of Masan. In other marine facilities, 4 facilities were reported to Donghae regional office, 3 facilities to Masan regional office, 2 facilities to Yeosu and Pyeongtaek regional offices, respectively, 1 facility to Incheon and Ulsan regional offices, respectively, and none of facilities to the other regional offices. In integrated marine science base facilities, 3 facilities were reported to Jeju regional office, 1 facility to Yeosu, Ulsan and Gunsan regional offices, respectively, and none of facilities to the other regional offices. The management based on the circumstances of regional offices, the management based on the characteristics of the type of facilities, the amendment of the relevant rules and regulations, facility owner's full knowledge and observance of the relevant rules and regulations with regard to the relevant type of facilities, and positive management actions from national point of view were proposed for national management plans of marine facilities.