최근 국내외적으로 LNG를 포함한 친환경 에너지에 대한 관심이 급증하여 LNG 취급시설 및 선석 개발이 활발히 진행되고 있다. 울 산항은 동북아 오일 및 에너지 허브 항만으로 선정되어 LNG 및 오일 저장시설과 선석을 개발 중이다. 현재 울산신항 북항지구에 건설 중인 LNG 터미널은 기존의 주요 부두 형태인 돌핀식이 아닌 안벽식 터미널로 건설 중이나 국내외적으로 안벽식 LNG 터미널의 계류시스템 배치에 대한 설계 기준이 없는 실정이다. 그러므로 본 연구에서는 안벽식 LNG 터미널의 계류시스템 설계 기준을 마련하기 위해 항만 및 어항 설계기 준에서 돌핀 형태의 계류시스템 배치를 반영한 부두를 개발하여 실제 접안대상 선박에 대한 계류 평가 요소의 민감도를 분석하였다. 분석 결 과, 기존 안벽식 부두의 계류시스템 배치와 비교하여 동일한 환경조건에서 계류삭 장력, 계선주 하중, 계류라인 수직각도, 방충재 반력, 선체 6 자유도 운동값이 대체로 감소하여 선박 및 부두의 안전성 향상에 유리한 것으로 분석되었다. 본 연구 결과는 안벽식 LNG 터미널의 설계 기준 개발을 위한 기초자료로 활용될 수 있을 것이다.

In the maritime industry, most perceptions, frameworks and methodologies of dealing with hazards are for their risk assessment rather than their risk management. This tendency discloses the reality that within the maritime sectors in areas like shipping, logistics, oil and gas there is a lack of coherent Quantitative Risk Management (QRM) methodology from which to understand the risk-based decisions especially for appropriate risk management such as in seaports’ terminals. Therefore, in this paper initially, during priority assessment of the identified hazards, Fuzzy Set Theory was applied to handle imprecision of the uncertain risk-based statistics to get an accurate result. In the next stage, Fuzzy Fault Tree and Fuzzy Event Tree methods were used to achieve the sequence of quantitative risk analysis. In the final step, a Fuzzy Technique for Order of Preference by Similarity to Ideal Solution tool was used for the implementation of the mitigation phase to complete and conclude the proposed QRM cycle.

The Port of Pyeong Taek is located on the west coast, meaning that the difference between the rise and fall of tide is great (flood tide 1.8 to 2.9 knots, ebb tide 1.6 to 2.9 knots). Due to mainly N~NW’ly strong winds & high waves during winter, navigating as well as loading & discharging vessels must focus on cargo handling. The strong tidal and wind forces in the Port of Pyeong Taek can push an LNG carrier away from its berth, which will end up causing forced disconnection between the vessel’s cargo line and shore-side loading arm. The primary consequence of this disconnection will be LNG leakage, which will lead to tremendous physical damage to the hull and shore-side equipment. In this study, the 125K LNG Moss Type ship docked at No. 1 Pier of the Pyeong Taek is observed, and the tension of the mooring line during cargo handling is calculated using a combination of wind and waves to determine effective mooring line and mooring line priority management. As a result if the wind direction is 90° to the left and right of the bow, it was found that line monitoring should be performed bearing special attention to the Fore Spring Line, Fore Breast Line, and Aft Spring Line.

UPS system in the liquefied natural gas(LNG) receiving terminal is one of the fundamental equipment that need to sustain operation during earthquake. In this study, modal identification test of UPS system was performed based on IEEE Std. 693-2005 and natural frequencies and modal damping, mode shapes had been identified. In addition, tri-axial time history test was performed to check the behavior and stress of the equipment during earthquake. Eigenvalue analysis was performed and analysis model was modified by reflecting the results of the test. Static analysis by dead weight and response spectrum analysis were performed to compare the combined stresses with the stress results of test. Dynamic characteristics and combined stresses under seismic load condition of the improved analysis model were similar to the test results and in this regard the compatibility was proved.

This study aims at examining the safety of the would-be approach channel of LNG Terminal at Kwangyang Harbour, by utilizing Captains 2000 port-design simulator. Six competent shipmasters or navigators participated in this study. The developed model ship was a 70,200DWT (138,000m3) LNG carrier. The environmental conditions were maximum flood-and-ebb current condition and wind condition. To evaluate the navigational safety, two categories were analyzed, which were measures of vessel's proximity and shiphandler's subjective evaluations. With respect to the effects of the worst environmental conditions on transit safety, it was concluded that the would-be approach channel was safe on basis of the support of four tugs of 3,200hp or more and current speed of 0.5knots or less.