• Journal of the Society of Naval Architects of Korea
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• v.55 no.5
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• pp.379-384
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• 2018

This study showed the development process of structural design method of BHB(Blast Hardened Bulkhead) which are applicable in preliminary design stage. In the previous 1st report, the simplified structural scantling equations of BHB were formulated theoretically using the modified plastic hinge method supplemented by considering the membrane effects due to large plastic deformation. And the scantling methodology of plate thickness and section area of stiffeners of the curtain plate type BHB was dealt with. In the present 2nd report, derivation process of the correction factors which can adjust the developed scantling equations considering the uncertainties contained in the design parameters was introduced. Considering the actual BHB structures of 3 warship, the correction factors for the developed scantling equations for curtain plate type BHB were derived. Finally the applicability, validity of them and the strategy of future improvement were considered.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.2
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• pp.155-160
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• 1993

A design method for web frame scantling on engine room structures was described. The parameters determining the scantling of web frame were studied on the basis of the empirical ship's data. It is found that the parameters determining the scanting of web frame consist of tween deck height, main engine and propeller excitation frequency, scantling draft, web frame spacing, the number of decks and main engine BHP etc. And a formula proposed by empirical ship's data was established in view points of static and dynamic structural behavior. In this study, it can be shown that at initial design stage, a method for web frame scantling of engine room structure is provided as very practical design processes.

• Journal of the Society of Naval Architects of Korea
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• v.31 no.4
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• pp.130-138
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• 1994

Bottom plates of empty hold are subjected to not only water pressure but also bi-axial inplane loads, specially in the alternate full loading full loading condition of bulk carrier. This kind of plate behaviours is very difficult to be explained and to be estimated using common buckling design guide in the initial design stage of hull structure, therefore, some more concrete studies for this plate structure was performed based on the currently developed buckling estimation formula. In this buckling formula, torsional stiffness effects of edge stiffener are included additionally and effects of elastic buckling strength of plate panel are treated as characteristic value problem. Also considering boundary stiffener effects and inplane and lateral loading, evaluation of bottom plate scantling using this formula, calculated results using various classification regulation of buckling strength and results of first report approach are compared each other and useful guides using developed formula for bottom plate scantling design are discussed.

• Journal of the Society of Naval Architects of Korea
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• v.30 no.4
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• pp.112-126
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• 1993

In this paper, unified requirements of IACS on longitudinal strength of ships are investigated using nonlinear wave loads analyses under short term irregular waves. Also, analyses on IACS wave data were carried out for the purpose of presenting the guideline for future use. While keeping theoretical consistensy, the rule requirements for horizontal shear force, bending moment and torsional moment are newly proposed for the ships of large deck openings bases on the calculation results for 17 sample ships. The requirements for side shell hydrodynamic pressure are also presented. All the calculated results are compared with other Societies and present KR rules. These formula will be checked when corresponding requirements of structural scantling are determined.

• Journal of Ocean Engineering and Technology
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• v.23 no.5
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• pp.71-78
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• 2009

In ship design or offshore structure design, the evaluation of buckling strength (or ultimate strength) is critical to the determination of scantling of stiffened plates. For this reason, it is useful to study the effect of applying different formula or the relationship between stiffened plate with buckling utilization factor (UF). It can facilitate a designer to decide how much the scantling should be reinforced or how much can be reduced for an optimal design. This paper conducts a comparative study for three buckling check methods; DNV-Ship-Rule, DNV-RP-C201, DNV-PULS. The capacity curves and 2D contour plot for utilization factors versus bi-axial in-plane stresses are compared. The contour plots of DNV-Ship-Rule and DNV-PULS show smoothly increasing trends of UF as the applied in-plane stresses increase, however that of DNV-RP-C201 shows rapidly increasing trend as the applied stresses go beyond transverse buckling stress. A sensitivity analysis is performed to investigate the influence level of each parameter of a stiffened plate on UF. Resulting from the analysis, plate thickness is identified to be the most affective parameter to UF regardless of the buckling check methods. Based on the addressed study, optimal designs for bottom plate of 165 K tanker corresponding to three formulas are compared with each other. DNV-PULS yields 1 mm and 2 mm less thickness than DNV-Ship-Rule and DNV-RP-C201, respectively.