• 대한조선학회논문집
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• 제48권2호
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• pp.165-170
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• 2011

In this paper, wind force coefficient by wind tunnel experiment is obtained to compute the accurate wind force of the gantry crane model to be used for mobile harbor ship. The first crane model was tested under 20, 30, 40, 52m/s, partially 58m/s and the wind force coefficient is about 2.0 which is very close to the suggested theoretical value. The other is the more reliable crane model and tested under 20, 30, 40m/s also giving the similar realistic wind force coefficient. Also structural analysis of crane model was performed giving the reliable stress level. Since the rolling effect is important for mobile harbor ship, the safety of the crane on the ship needs to be guaranteed. For this, using the computed reaction forces, a tie-down design is suggested which connects the crane and ship to resist the turnover motion of the crane.

• 한국해양공학회지
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• 제17권6호
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• pp.16-22
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• 2003

In this paper, the method of determining the economically-optimal design section of rubble mound breakwater, using ADS program, was studied to supplement the deterministic approach. First of all, the design waves are computed, according to the return periods, using the Weibull distribution from the data of waves at the location of the breakwater. In order to take an optimal section, according to the return periods, the ADS program was used. The restriction conditions and objective functions are decided from the references of the specifications and standard manuals for Coastal and Harbor Construction Work. Results from this study support the ADS program as an appropriate method for determining the economically-optimal section of rubble mound breakwater, comparing the construction costs and the initial and damage repair costs for its life time.

• 한국실내디자인학회논문집
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• 제19권3호
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• pp.172-179
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• 2010

The Sydney Opera House is built on a peninsula of rock that juts out into Sydney Harbor. The site was once a landing place for ships. Utzon, Architect, designed the theatres for the Opera House to fit the shape. The two theatres were placed side by side so that they both had extensive harbor views. The Sydney Opera House is designed the foyers to take full advantage of these sights. Because the building would be seen from all sides, even from above, it was to be a piece of sculpture. The outside was as important as the inside. The audience enters from behind the stage and walks around to the foyers overlooking the harbour. The wing and backstage areas are small because of the way the foyers wrap around the theatre. The stage is made up of large platform lifts which provide the vertical movement for changing scenery. The sets come up from the workshops below stage. The flytower fits under the largest roof shell and doesn't break the skyline. The important elements are the podium, the shells and the reminders. The podium, the huge monolithic concrete structure, contains hundreds of rooms and nearly all the technical equipment. The podium is clad with pink granite slabs and seen from the water. This design eliminated a maze of fire escape stairs and, at the same time, gave people a wonderful view of the harbour. The egg shell is remarkably strong and express the form as the symbol of the site.

• 한국해안해양공학회지
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• 제19권2호
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• pp.136-145
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• 2007

파랑이 수중 천퇴부를 넘어 쇄파하는 경우 파고는 작게 형성되나 강한 이차적 흐름 (쇄파유도류)이 발생한다. 따라서, 임의의 해양구조물이 쇄파대에 위치할 경우에는 단순히 가시적인 파고에만 근거한 파력산정은 과소설계를 초래할 가능성이 있으며 구조물의 안정설계를 위해서는 쇄파유도류의 유속이 가미된 상태에서의 유체력을 정확히 산정하여 반영할 필요가 있다. 본 연구에서는 Boussinesq 방정식 모델을 이용하여 쇄파대내에서의 파고분포와 쇄파유도류를 계산하는 기법을 수립하였으며 과거에 수행하였던 이어도 해양과학기지의 수리모형실험 (1/120)의 모델영역에 적용하였다. 이 계산결과를 이용하여 모형구조물에 작용하는 유체력을 계산하고 수리모형실험 결과와 비교함으로써 쇄파유도류의 영향을 정량적으로 평가하였다.

• 한국해안·해양공학회논문집
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• 제22권2호
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• pp.112-119
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• 2010

안전율을 이용하여 항만 구조물의 임의의 파괴모드에 대한 목표파괴/안전수준을 산정할 수 있는 Monte-Carlo 모의법이 제시되었다. 본 연구에서 제안한 해석법은 기존의 해석법과 다르게 단순히 결정론적 설계법으로 설계된 안전율에 대한 자료만을 이용하여 목표파괴/안전수준을 설정할 수 있다. 결정론적 설계법에서 사용되는 안전율과 신뢰성 설계법에서 사용되는 신뢰지수를 직접적으로 연결시켜줄 수 있는 수학적 모형들이 수립되었다. 비록 제한적인 자료를 사용하였음에도 불구하고 수립된 모형들을 직립 방파제의 활동 파괴모드에 적용하여, 유의목표파괴 수준이라는 개념으로 본 연구에서 산정한 직립 방파제의 활동 파괴모드에 대한 목표파괴수준이 최근 일본에서 제안된 결과와 매우 잘 일치하였다.

• 한국연안방재학회지
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• 제5권4호
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• pp.163-172
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• 2018

To propose the design technique and the execution manual of the LWFS(Lightweight Foamed Soil) method using dredged soil, the operation system for the test-bed integrated management, and to establish an amendment for the domestic quantity per unit and specifications, and a strategy for its internationalization. In order to utilize the dredged soil from the coastal area as a construction material, we constructed the embankment with LWFS on soft ground and monitored its behavior. As a result, it can be expected that the use of LWFS as an embankment material on the soft ground can improve the economic efficiency by reducing the depth and period of soil improvement as well as the uses of nearby dredged soil. To verify the utilization of the dredged soil as a material for light-weighted roadbed, soft ground and foundation ground, and surface processing, perform an experimental construction for practical structures and analyze the behavior. It is expected to be able to improve the soft ground with dredged soil and develop technique codes and manuals of the dredged soil reclamation by constructing a test-bed in the same size of the fields, and establish the criteria and manual of effective dredged soil reclamation for practical use. The application technology of the dredged soil reclamation during harbor constructions and dredged soil reclamation constructions can be reflected during the working design stage. By using the materials immediately that occur from the reclamation during harbor and background land developments, the development time will decrease and an increase of economic feasibility will happen. It is expected to be able to apply the improved soil at dredged soil reclamation, harbor and shore protection construction, dredged soil purification projects etc. Future-work for develop the design criteria and guideline for the technology of field application of dredged soil reclamation is that review the proposed test-bed sites, consult with the institutions relevant with the test-bed, establish the space planning of the test-bed, licensing from the institutions relevant with the test-bed, select a test-bed for the dredged soil disposal area.

• 한국해안해양공학회지
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• 제17권2호
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• pp.98-105
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• 2005

비교적 설계파가 낮고 지반이 연약한 경우에 적합하면서도 저렴하고 안전하게 시공할 수 있는 새로운 방파제 형식의 개발하였는데, 이 구조형식은 지반굴착공사에 널리 쓰이는 가로널식 말뚝과 유사한 형태이다. 이러한 새로운 형식의 방파제에 대한 구조거동은 수치해석을 통하여 평가할 수 있지만, 가로널과 말뚝 연결부의 비선형성, 재료의 비선형성, 지점조건의 비탄성 등으로 인하여 실제 현장의 구조거동과 수치해석상의 구조 거동은 차이가 있을 수 있다. 이러한, 수치해석과 현장거동사이의 구조거동의 차이를 살펴보기 위해서 본 논문에서는 수조모형 실험을 수행하여 파고, 지점조건, 앵커 케이블의 숫자에 따른 구조거동을 살펴보고 그 값을 수치해석 결과와 비교하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 추계학술대회
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• pp.708-713
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• 2004

This research develops a sensorless hydraulic servo system of Parallel-Typed robot for harbour construction. Purpose of the robot is to mechanize the construction, which is accomplished through a joystick's operating by a stoneworker (or diver). The robot is attached on the end of an excavator as its attachment or transported by a crane to reach the desired place. The embedded compact controller is installed on the robot body and controlled by wireless telecommunication. For underwater work, it is necessary to waterproof the robot and its sensors. Especially, a sensor waterproof is a main drawback for the underwater robot. This leads us to develop a hydraulic robot position controller using an observer which gives the position information without any position sensor. We design a neural network to identify the displacement change according to the command voltage to servo valve. To verify the sensorless controller, this paper presents the performance of the sensorless control for which the position is given by the observer comparing with that of the sensor control for which the position is measured by LVDT sensors.

• 지질공학
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• 제13권3호
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• pp.359-368
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• 2003

현재 건설중에 있는 부산 신항만의 매립을 위해 채석장이 가동중에 있으나, 실제 공사 중 채석된 암석이 당초 설계와는 다른 암질을 포함하고 있다. 따라서, 당초 설계와는 달리 많은 폐석이 발생되어 정상적인 공사추진에 애로사항이 있으므로, 현장조사 및 실내작업을 통하여 지정된 채석장에 대한 전체적인 암질을 구분하는 것이 본 연구의 목적이다. 이를 위해 측량, Schimidt Rock Hammer 시험, 절리간격조사를 시행하였고 실내에서 DIPS 및 Rockworks 프로그램을 이용하여 절리의 방향성 및 발파 후 암괴의 크기를 분석하였다. 그 결과 본 지역에는 절리밀도가 높아 토석 채취시 ${\Phi}100mm$ 이하의 필터사석이 많이 발생하는 것으로 분석되었다.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2004년도 춘계학술발표회
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• pp.197-202
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• 2004

In order to design accurately sand compaction pile (SCP) method with low replacement area ratio, it is important to understand the mechanical interaction between sand piles and clays and its mechanism during consolidation process of the composition ground. In this paper, a series of numerical analyses on composition ground improved by SCP with low replacement area ratio were carried out, in order to investigate the mechanical interaction between sand piles and clays. The applicability of numerical analyses, in which an elasto-viscoplastic consolidation finite element method was applied, could be confirmed comparing with results of a series of model tests on consolidation behaviors of composition ground improved by SCP. And, through the results of the numerical analyses, each mechanical behaviors of sand piles and clays in the composition ground during consolidation was elucidated, together with stress sharing mechanism between sand piles and clays.