• Bulletin of the Society of Naval Architects of Korea
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• v.2 no.1
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• pp.3-8
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• 1965

The objects of this paper are to stimulated discussion of the criteria used for deciding the scantling of watertight bulkhead stiffener of steel fishing boats ranged of length of 20 meters to 80 meters and to suggest a method of calculation based on beam theory. Present knowledge is examined and it appears that failure of a bulkhead stiffener is comparatively rare. Regarding its structure bulkhead does not contribute on longitudinal strength of a ship. The strength of a bulkhead stiffener can be treated locally. Assuming bulkhead stiffeners are free ends and fixed ends theoretical required section modulus are calculated and compared with classification societies' rule. Welding effect of a bulkhead stiffener to bulkhead plate and a bracket to stiffener and deck plate are considered. On various conditions of joints are suggested.

• Journal of Korean Port Research
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• v.14 no.2
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• pp.219-231
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• 2000

In this paper a complicated structural behavior in collision and its effects of energy translation to the collision bulkhead was examined through a methodology of the numerical simulation to obtain a ideal bow construction and a location of collision bulkhead against head on collision. In the present the bow structure is normally designed in consideration of its specific structural arrangements and internal and external loads in these area such as hydrostatic and dynamic pressure, wave impact and bottom slamming in accordance with the Classification rules, and the specific location of collision bulkhead by SOLAS requirement. By these studies the behavior of the bow collapse due to collision was synthetically evaluated for the different size of tankers and its operational speed limits, and by the results of these simulation it provides the optimal design concept for the bow construction to prevent the subsequent plastic deformation onto or near to the collision bulkhead boundary and to determine the rational location of collision bulkhead.

• Special Issue of the Society of Naval Architects of Korea
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• 2011.09a
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• pp.21-24
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• 2011

Oil Tight Bulkhead (O. T. Bulkhead) is one of the most important structural members of oil tankers in the views of vessel's strength and safety. Therefore O.T. bulkhead's strength should be sufficient against relevant loadings, which is normally verified by local scantling requirement and structural strength analysis defined in CSR (Common Structure Rules for Double Hull Oil Tankers). However, there is a weak-able situation when the vertical stiffeners are cut due to the penetration of cargo pipes through O. T. Bulkhead. In addition, CSR does not define how to prove the strength of this case. Therefore it is necessary to verify the structural adequacy in case that several vertical stiffeners are discontinued. This article intends to prove the strength of O. T. Bulkhead with five (5) vertical stiffeners discontinued due to pipes' penetration using the grillage analysis and the finite element analysis and to provide proper reinforcement.

• Bulletin of the Society of Naval Architects of Korea
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• v.1 no.1
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• pp.3-8
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• 1964

The classification society rules [1], [2], [3], [4] on the thicknesses of the bulkhead platings are represented graphically. Fig. 1 shows that every rule value for the thickness of the ordinary watertight bulkhead plating is than theoretical value calculated by Timoshenko's formula (1) for ${\sigma}_y=35,000$ psi and ｋ=0.4998. When a flooding due to damage occurred, however, the stiffened edges would yield and clamped edges would change to plastic hinges. In such case, the maximum bending stress at the clamped edges are reduced considerably. The rule values, therefore, are supposed to be acceptable in spite of their insufficient scantlings compared with the values calculated by (2). In the ordinary watertight bulkhead platings A.B.S. Rules give the largest scantlings of all. Fig. 2 shows that A.B.S. Rules and K.R.-N.K. Rules give larger values than the calculated by (2) for deep tank bulkhead platings. But Lloyd Rules give the smaller thickness than equation (2). The special requirements for corrosion bulkhead platings are not studied here.

• Journal of the Society of Naval Architects of Korea
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• v.29 no.3
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• pp.157-165
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• 1992

Three dimensional structural analysis is carried out to evaluate the global behavior of the platings for the watertight bulkhead and deep tank bulkhead of the selected model ship and to analyze the theoretical background of their formulations for the bulkhead platings in the Rules of each classification societies. In this study, coarse and fine mesh analysis for transverse bulkhead is carried out to know the stress distribution in way of the concerned areas and that result is presented to show the back data for the new formulations of such transverse bulkhead platings.

• Journal of Ocean Engineering and Technology
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• v.14 no.2
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• pp.28-35
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• 2000

In this paper a complicated structural behavior in collision and its effect of energy transmission to the collision bulkhead was examined through a methodology of the numerical simulation to obtain a ideal bow construction and a location of collision bulkhead against heat on collision. At present the bow structure is normally designed in consideration of its specific structural arrangement and internal and external loads in these areas such as hydrostatic and dynamic pressure wave impact and bottom slamming in accordance with the Classification rules and the specific location of collision bulkhead by SOLAS requirement. By these studies the behavior of the bow collapse due to collision was synthetically evaluated for the different size of tankers and its operational speed limits and by the results of these simulation it provides the optimal design concept for the bow construction to prevent the subsequent plastic deformation onto or near to the collision bulkhead boundary and to determine the rational location of collision bulkhead.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.20 no.6
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• pp.33-43
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• 2021

A60 class bulkhead penetration piece is a fire resistance system installed on a bulkhead compartment to protect lives and to prevent flame diffusion in a fire accident on a ship and offshore plant. This study focuses on the approximate optimization of the fire resistance design of the A60 class bulkhead penetration piece using a multi-island genetic algorithm. Transient heat transfer analysis was performed to evaluate the fire resistance design of the A60 class bulkhead penetration piece. For approximate optimization, the bulkhead penetration piece length, diameter, material type, and insulation density were considered discrete design variables; moreover, temperature, cost, and productivity were considered constraint functions. The approximate optimum design problem based on the meta-model was formulated by determining the discrete design variables by minimizing the weight of the A60 class bulkhead penetration piece subject to the constraint functions. The meta-models used for the approximate optimization were the Kriging model, response surface method, and radial basis function-based neural network. The results from the approximate optimization were compared to the actual results of the analysis to determine approximate accuracy. We conclude that the radial basis function-based neural network among the meta-models used in the approximate optimization generates the most accurate optimum design results for the fire resistance design of the A60 class bulkhead penetration piece.

• Proceedings of the Korea Committee for Ocean Resources and Engineering Conference
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• 2000.04a
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• pp.195-204
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• 2000

In this paper a complicated structural behavior in collision and its effect of energy translation to the collision bulkhead was examined through a methodology of the numerical simulation to obtain a ideal bow construction and a location of collision bulkhead against head on collision. In the present the bow structure is normally designed in consideration of its specific structural arrangements and internal and external loads in these area such as hydrostatic and dynamic pressure, wave impact and bottom slamming in accordance with the Classification rules, and the specific location of collision bulkhead by SOLAS requirement. By these studies the behavior of the bow collapse due to collision was synthetically evaluated for the different size of tankers and its operational speed limits, and by the result of these simulation it provides the optimal design concept for the low construction to prevent the subsequent plastic deformation onto or near to the collision bulkhead boundary and to determine the rational location of collision bulkhead.

• Proceedings of the Korean Society of Propulsion Engineers Conference
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• 2017.05a
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• pp.440-444
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• 2017

Two-dimensional hydrodynamic analysis was performed to analyze the attenuating characteristics of shock waves generated by the detonation of the bulkhead initiator. Through the interlocking analysis between HNS and HMX stacking initiator and STS bulkhead, we have precisely simulated detonation growth and pressure wave attenuation phenomena. The free surface velocity at the surface of the bulkhead was measured for quantitative comparison with the test data by VISAR. As a result, it was confirmed that the pressure attenuating pattern of the shock wave exponentially decreased according to the bulkhead thickness. The observed inflection point at the particle velocity measured over time is due to the subsequent propagation of the shock wave due to the rapid spallation of the interface between the detonator and the bulkhead.

• Journal of the Society of Naval Architects of Korea
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• v.40 no.4
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• pp.53-58
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• 2003

Design of the corrugated watertight bulkhead for a bulk carrier is principally determined by the permissible limit of Classification requirements. As the weight of upper and lower stool has considerable portion of the total weight of the transverse bulkhead, optimum design including the stool geometry and size will play an important role on economic shipbuilding. The purpose of this study is focused on the minimization of steel weight using the design variables, which are the shape and the size of the corrugation as well as the upper and lower stools. Discrete variables are used as design variables for the practical design. In this study, the evolution strategies (ES), which can highly improve the possibility of leaching the global minimum point, are selected as an optimization method. Usefulness of this study is verified by comparison with the proven type ship design. As objective function, total weight of the transverse bulkhead including the upper and lower stools is used.