• Proceedings of the KWS Conference
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• 1999.05a
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• pp.20-23
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• 1999

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.335-338
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• 2009

일반적으로 비중이 큰 철광석이나 석탄 등을 운반하는 선박화물선의 호퍼 너클 이음부는 여러 판이 용접되어 복잡한 형상을 가지고 있어 응력이 집중되어지므로 피로강도평가 시 많은 문제점이 노출되는 구간이다. 이번 연구에서는 기존 sloping 방식의 호퍼 너클 이음 부를 갖는 180k 산적화물선 표준 모델과 제안 되어진 round 방식의 호퍼 너클 이음 부를 갖는 산적화물선에 대하여 구조강도평가와 피로강도평가를 수행하였다. 이때 합리적인 비교를 위하여 제안되어진 모델은 기존의 표준 모델의 화물창과 발라스트창의용적이 일치하도록 제안하였다. 또한 CSR을 기반으로 한 하중들에 대하여 허용응력과 25년 피로수명을 만족하도록 구조부재를 결정하였으며 피로강도평가 결과를 바탕으로 호퍼 너클부의 변화에 따른 선각 중량과 상대 건조 비 개념을 이용하여 보다 효율적인 구조를 제시 하였다.

• Journal of the Korean Society for Advanced Composite Structures
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• v.2 no.2
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• pp.13-19
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• 2011

This paper presents the stress distribution of the damaged butt joint of steel plate using CFRP laminates when the flange in tension zone of steel box girder is welded by butt welding. When CFRP sheets are patched on tension flange of steel-box girder, the stress distribution of a vertical and normal direction on damaged welding part is shown as parameters such as a variation of the thickness of adhesive, the overlap length with steel, and the modulus of elasticity of CFRP sheets. For the study, we wrote the computer program using the EAS(Enhanced assumed strain) finite element method for plane strain that has a very fast convergency and exact stress for distorted shape.

• Proceedings of the KWS Conference
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• 1997.05a
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• pp.78-80
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• 1997

• Journal of Welding and Joining
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• v.18 no.4
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• pp.1-3
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• 2000

• Proceedings of the KWS Conference
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• 1994.10a
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• pp.82-84
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• 1994

• Journal of Korean Society of Steel Construction
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• v.16 no.4 s.71
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• pp.479-492
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• 2004

When U-ribs of steel deck plates are connected at the field, overhead welding should be done with backing strips. Misalignments may occur and lead to eccentric moments as well as high stress concentrations at welded joints. In this study, stress analyses and fatigue tests were carried out. Stress analyses for U-ribs' welded joints with backing strips were performed with different misalignments, root shapes, root gaps, and backing strip sizes. From the stress analyses, the stress concentration factors increased with increasing misalignments and root gaps. With the fixed misalignments and root gaps, the stress concentration factors obtained in the case of the semi-circle root shape were lower than those in the case of the right-angle root shape. It was verified that backing strip sizes have little influence on stress concentration factors. The fatigue tests for U-ribs' welded joints with backing strips indicated that increased misalignments shorten fatigue life drastically and cracks usually initiate at the root of the base metal and are propagated to the weld bead surface. Based on the results of the stress analyses, root-shape control methods were developed to mitigate stress concentration by changing welding condition control, radius curvature, and flank angle.

• Journal of the Korea Concrete Institute
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• v.15 no.3
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• pp.425-432
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• 2003

The joint treatment of concrete is one of the technical problems in concrete constructions. Joints created with concrete constructions result in serious weakness in the aspects of both structural and water-barrier function. The radar and the infrared thermography method have been used for the non-destructive inspection of several construction joints of concrete structures in this study. The advantages and limitations of these methods are investigated for non-destructive inspection on construction joints of concrete columns. It can be shown that the detecting precision of construction joints using these methods is improved if radar analysis is carried out with a simulation analysis. In case of the infrared thermography method, the shape of construction joints can be also detected when heating is performed before testing. As the result, it has been verified that the construction joints, difficult to be detected by visual inspection, could be inspected effectively in broad areas at short period of time when these two methods are applied.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.484-487
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• 2010

본 논문에서는 BIM(Building Information Modeling)의 핵심기술인 파라메트릭 기술을 기반으로 하여 철근콘크리트 구조물의 기둥부재 주철근 자동배근시스템을 구축함으로써 기존 프로그램에서 사용자가 직접 입력해야하는 변수의 수를 최소화하고 사용성과 정확성을 높이는 것을 목적으로 한다. 기존 철근배근 형상 자동 모델링에서 기둥철근의 자동 모델링은 기둥단면이 변하는 부분에서의 철근 배근과 정착 및 이음길이를 고려하지 않고 있다. 만약 고려하더라도 이용자가 직접 입력하는 방식이기 때문에 규모가 큰 건물일 경우 방대한 정보의 처리 미숙으로 인해 정확한 모델링을 기대하기 어려운 실정이다. 본 연구에서는 기둥 부재에 대하여 대상 건물을 선정하고 구조해석 모델링을 구축한 후 구조해석 결과 데이터베이스를 추출하여 얻은 정보와 건축구조설계기준에 따른 정착 및 이음 길이 산정에 관한 알고리즘을 구축하여 철근배근 형상 자동화 모듈에 적용하여 배근 자동 설계 및 자동 형상화 모듈을 생성하였다.

• Proceedings of the KWS Conference
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• 1996.05a
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• pp.154-158
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• 1996