• Journal of Ocean Engineering and Technology
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• v.25 no.3
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• pp.1-10
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• 2011

This paper estimates the residual longitudinal strength of a damaged double hull VLCC (Very Large Crude Carrier) under combined vertical and horizontal bending moments using Smith's method. The damage estimated in this study occurred due to collision or grounding accidents. The effects of the randomness of the yield stress, plate thickness, extent of damage, and the combination of these three parameters on the ultimate hull girder strength were investigated. Random variables were generated by a Monte Carlo simulation and applied to the double hull VLCC described by the ISSC (International Ship and Offshore Structures Congress) 2000 report.

• Bulletin of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.17-30
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• 1993

세계 조선소 중 최근에 single hull VLCC를 가장 많이 건조한 경험을 바탕으로 4척의 double side VLCC를 성공리에 인도하여 선주측으로부터 호평을 받고, 나아가 전 세계 최초로 double hull VLCC의 2척 동시 진수라는 성과를 거둘 수 있었던 것은, 각 type의 특성을 고려한 최적의 구\ulcorner/생산설비 및 작업환경 등을 고려한 개선사항을 설계에 적극 반영한 결과로 나타난 것이다. 최근에 신규 수주 상담이 진행되고 있는 double hull VLCC 선주들의 대부분은 당사에서 single hull VLCC를 건조한 경험이 있는 선주들로서, 그동안 고객 만족을 위한 운항, 보수, 점검, 통해, 안전 및 편의성 등 선박 성능향상 측면에서 노력한 결과로 볼 수 있으며, 여기에서 만족하지 않고 당사의 Motto인 VOF( Vessel do the First Class) 구현을 이루고자 최선을 다하고져 한다.

• Journal of Ship and Ocean Technology
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• v.5 no.4
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• pp.19-28
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• 2001

A comparative study of the new flexible double hull structure is presented as a collision energy absorbing system, which is constructed with mixed stringers comprising slant and straight stringers for the double hull tanker, The dimension and disposition of this mixed stringers are selected to give the maximum absorbing energy. From the viewpoint of collision energy absorbing efficiency, this structural system is compared with three other types of the double hull constructions with trapezoidal stiffener, stringer type and standard type of VLCC, 310K DWT, Based on the constant hull weight, the proposed double hull structure with mixed stringers shows a improved crashworthiness as the results.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.123-131
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• 1993

Since the years of oil tanker production in the 70's, the concern of marine enviromental protection is worldwidely increased, at last it is compulsorily ruled to product the double hull tanker by International Maritime Organization(IMO). Throughout these informative years Daewoo Shipyard has developed the double hull VLCC for a future vessel. The paper presents hull design for 300K double hull VLCC which was carried out to satisfy with statutory requirement of it, focused the structural arrangement and direct calculation in cargo hold area.

• Journal of Ship and Ocean Technology
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• v.3 no.1
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• pp.12-26
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• 1999

A new concept of collision energy absorbing system for ;he New Oil-tankers with Advanced Double Hull Structure(NOAHS and NOAHS II) are presented through the joint-research pro-gran between Inha and Hamburg-Harburg University. A comparative study on col vision resistance of these proposed side structures with standard double hull structure of 310K DWT class VLCC, is carried out. The fatigue investigation of structural detail parts is also included. It contains a comparative fatigue study based on pertinent regulations of Classification Societies.

• Journal of Hydrospace Technology
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• v.1 no.1
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• pp.89-110
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• 1995

The enactment of OPA90 (Oil Pollution Act of 1990) in the USA and the consequent moves by IMO(International Maritime Organization) to introduce new Regulations for the design of oil tankers led the oil transportation industry to undergo a period of big change. This resulted in the introduction of double hull tankers. This paper introduces the design for the 300, 000 DWT double hull VLCC of World-Wide Shipping Agency Pte Ltd. in Hong Kong, which is the first of this type constructed by Daewoo Shipbuilding & Heavy Machinery Ltd.(DSHM). The characteristics of the compartment and structural arrangement of this vessel are briefly described, and the scope of structural analysis is illustrated. In addition, the merits/demerits of different crosstie arrangements are described in the appendices.

• Journal of the Korean Society for Marine Environment & Energy
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• v.1 no.2
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• pp.82-95
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• 1998

In this paper, two series of numerical simulations are performed using LS/DYNA3D: The first series of numerical simulations are collision events between a 310,000 DWT double hull VLCC (struck ship) and two 35,000 and 105,000 DWT tankers (striking ships). Collisions are assumed to occur at the middle of the VLCC with the striking ships moving at right angle to the YLCC centerline. The second ones, grounding accidents of two 40,000 DWT Conventional and Advanced Double Hull lanker bottom structures, CONV/PD328 and ADH/PD328 models. The overall objective of this study is to understand the structural failure and energy absorbing mechanisms during collision and grounding events for double hull tanker side and bottom structures, which lead to the initiation of inner shell rupture and cause the kinetic energy dissipation to bring the ship to a stop. These numerical simulations will contribute to the estimation of damage extents of collision and grounding accidents and the future improvements in lanker safety at the design stage.

• Journal of the Korean Society of Marine Environment & Safety
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• v.3 no.1
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• pp.1-14
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• 1997

This paper describes a series of numerical simulations of colision between a 310, 000 DWT double hull VLCC (struck ship) and three 35, 000, 70, 000 and 105, 000 DWT tankers (striking ships) using LS/DYNA3D. Collisions are assumed to occur at the middle of the VLCC with the striking ships moving at right angle to the VLCC centerline. Striking ship speeds are varied to find a critical speed without failure of inner side shell, and the informations of collision force and absorption energy of each case are also reported. The validation of LS/DYNA3D in this study was made by comparing the result of numerical simulation of LS/DYNA3D with that of double hull tanker grounding experiment by the Carderock Division of Navla Surface Warfare Center (CDNSWC).

• Special Issue of the Society of Naval Architects of Korea
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• 2005.06a
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• pp.84-89
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• 2005

The double hull VLCC(Very Large Crude Oil Tanker) have been designed to have each four(4) longitudinal bulkheads and transverse bulkheads in general. Actually, the inside longitudinal bulkheads among four(4) longitudinal bulkheads, which are extended up to the end of the aft cargo hold for continuity of the members, have been designed with knuckled type inboard due to the narrowed hull shape at bottom region, but sometimes the straight type of longitudinal bulkheads were adopted based on the degree of the hull lines shape. However, regardless the type of longitudinal bulkheads, inside and outside longitudinal bulkheads conflict each other in aft cargo hold region This makes the structure more complex thus giving difficulties to structural design and production. Recently, a vessel of straight type was reported to have cracks on bracket end and tripping bracket toe in aft cargo hold region. As a solution to this problem, in designing the first 60m Beam VLCC, DSME developed a new cargo hold structure which is good in production and structural point of view by structural strength and fatigue analysis of fore and aft cargo hold.

• Structural Engineering and Mechanics
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• v.42 no.4
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• pp.531-549
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• 2012

Numerous oil tanker losses have been reported and one of the possible causes of such casualties is caused by the structural failure of aging ship hulls in rough weather. In aging ships, corrosion and fatigue cracks are the two most important factors affecting structural safety and integrity. This research is about effect on hull girder ultimate strength behavior of double hull oil tanker according to corrosion after Part I: stiffened panel. Based on corrosion data of Part I (time-dependent corrosion wastage model and CSR corrosion model), when progressing corrosion of fourtypes of double hull oil tankers (VLCC, Suezmax, Aframax, and Panamax), the ultimate strength behavior of hull girder is compared and analyzed. In case of the ultimate strength behavior of hull girder, when occurring corrosion, the result under vertical and horizontal bending moment is analyzed. The effect of time-dependent corrosion wastage on the ultimate hull girder strength as well as the area, section modulus, and moment of inertia are also studied. The result of this research will be useful data to evaluate ultimate hull girder strength of corroded double hull oil tanker.