• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.322-325
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• 2010

철강 플랜트 주요 설비인 전로를 지지하는 장치의 접합부 강도설계를 위해 작용하중은 해석적인 방법으로 신뢰성 있게 계산하였고, 정적하중에 의한 응력은 ASME 규정에 따른 허용응력으로 평가하였다. 한편 피로설계 측면에서는 전로와 같은 대형 용접구조물은 강도상 취약부인 용접부에서 다양한 용접비드 형상에 따라 국부응력이 크게 달라지므로 설계단계에서 피로수명 평가에 어려움이 있었다. 따라서 전로 지지장치 접합부 피로설계는 설계단계에서 피로수명을 평가하는 실용적이고 안전측 방법으로 알려진 Hot Spot 응력을 사용하고 공신력을 갖는 설계규정인 ASME와 영국 PD 5500 절차에 의해 평가하였다. 평가결과 두 규정 모두 안전측에서 평가되는 것을 확인할 수 있었고 이 방법은 피로하중이 지배적인 대형구조물의 설계단계에서 유용한 방법으로 활용할 수 있으리라 판단된다.

• Structural Engineering and Mechanics
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• v.81 no.6
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• pp.781-790
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• 2022

The present paper describes a general procedure of the structural safety assessment for the independent type C tank of LNG bunkering ship. This strength assessment procedure consists of two main scheme, global Finite Element Analysis (FEA) model primarily for hull structure assessment and detailed LNG Tank structures FEA model including the cylindrical tank itself and saddle-support structures. Two kinds of mechanism are used, fixed and slides constraints in fore and rear of the saddle-support structures that result in a variation of the reaction forces. Finite Element (FE) analyses have been performed and verified by the strength acceptance criteria to evaluate the safety adequacy of yielding and buckling of the hull and supporting structures. The detail of FE model for an LNG type C tank and its saddle supports was made, which includes the structural members such as cylindrical tank shell, ring stiffeners, swash bulkhead, and saddle supports. Subsequently, the FE buckling analysis of the Type C tank has been performed under external pressure following International Gas Containment (IGC) code requirements. Meanwhile, the assessment is also performed for yielding and buckling strength evaluation of the cylindrical LNG tank according to the PD 5500 unfired fusion welded pressure vessels code. Finally, a complete procedure for assessing the structural strength of 500 CBM LNG cargo tank, saddle support and hull structures have been provided.