• Nuclear industry
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• v.5 no.7 s.29
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• pp.30-35
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• 1985

원자력시설의 폐지조치에 따른 원자로 강구조물의 해체 또는 시설에서 발생하는 방사성고체폐기물의 감용처리 등 해체기술에 관한 연구개발의 필요성이 높아지고 있다. 이들 강구조물의 해체기술은 원자력시설 특유의 조건을 고려하여, 방사선방호의 관점에서 수중절단 또는 방사화된 두꺼운 재료의 원격절단을 고려한 공법을 취하여야 한다. 다음은 경수로형 원자력발전소의 원자로압력용기 및 로내구조물을 대상으로한 강구조물의 해체기술이다.

• Korean Journal of Construction Engineering and Management
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• v.8 no.3
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• pp.87-96
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• 2007

Recently construction environment is being professionalized. oversized and diversified. Due to fluctuation of construction environment, the demand for the project of steel structure is ieased gradually and steel construction is needed the efficient quality management. The construction of steel structure which required a variety of sub-contractors, the progress of works and technologies are comprehensive of various risks and uncertain factors. But currently the construction of steel structure is conducted the risk management by perception and experience of constructors. Therefore, the analyzing factors of the risk and establishing the device are able to manage the quality management efficiently. In this study, we have conducted the interview of experts, polls and through the Analysis Hierarchy Process (AHP) for the scientific and systematic risk management. This paper will propose a plan for systematization of the construction of the steel structure.

• Proceedings of the Korean Society of Tribologists and Lubrication Engineers Conference
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• 1996.05a
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• pp.47-52
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• 1996

본 연구에서는 각종 강구조물의 도장전 샌드블리스트 작업에 다른 공해를 방지하기 위해, 모래-물의 2상류를 분사할 수 있는 샌드블라스트 장치를 제작하여, 2상류 분사에 따른 마멸-부식(wear-corrosion)특성과 slurry erosion에 의한 anchor pattern 및 침식-마멸거동을 고찰하고, 물에 의한 강구조물의 부식방지를 위한 부식억제제가 강구조물의 도막에 미치는 방식특성을 구명함으로써 공해방지, 부식손상 및 산업의 국제경쟁력 향상에 기여하고자 한다.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.395-399
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• 2010

강구조 부재의 내화성능평가를 위한 비재하가열시험은 강재 허용온도로 평가되고 있으나, 강재의 허용온도 설정은 H형강 부재의 최대하중로 평가되는 한계용도와 고온에서의 강소재의 허용응력도 능력으로 설정되었으므로 실지 작용되는 강구조 부재의 하중조건과 다양한 부재의 종류 등의 관점에서 허용온도의 적용은 다소 불합리한 점이 있다고 판단된다. 따라서 본 연구에서는 강구조 건축물에서의 부재에 작용하는 하중에 따른 내화성능의 차이를 보이고 이에 따른 합리적인 내화성능 평가방법을 제안하고자 한다.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2009.04a
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• pp.557-560
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• 2009

본 연구에서는 건물의 규모, 용도 및 형식 등에 따라 다양하게 요구되는 성능에 대응할 수 있도록 하기 위한 성능설계에 대한 개념을 검증하고, 강구조 건축물의 특성을 고려한 성능레벨 및 성능한계에 대한 분류방법을 제안하였다. 또한 강구조 건축물의 경우 강도가 높고 경량인 특성에 의해 다른 구조형식에서는 크게 고려하지 않아도 되는 거주성능 및 진동특성을 제어하여 기능을 유지하기 위한 성능레벨을 설정하여 구조물이 항복하기 전의 성능레벨을 기능유지 및 무손상의 2단계로 제시하고, 이 때의 한계치를 기능한계 및 손상한계로 구분하였다. 강구조 건축물의 손상한계를 정의하기 위해 강구조 건축물의 설계 예를 이용하여 항복 층간변형각을 조사하였다. 그 결과 구조물의 손상발생을 억제할 수 있는 손상한계를 규정하기 위해 주로 사용하고 있는 층간변형각은 구조형식 및 설계방법에 따라 편차가 크게 나타나고 있으므로 손상한계치의 층간변형각을 임의로 설정하는 것은 매우 어려우며 향후 이에 대한 해석적, 실험적 검증이 필요할 것으로 판단되었다.

• Journal of Korean Society of Steel Construction
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• v.28 no.2
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• pp.85-96
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• 2016

Double split tee connection has various strength, stiffness, and energy dissipation capacity according to changes of thickness of T-stub flange and gauge distance, number, and diameter of high-strength bolt. If the double split tee connection is applied to a low- or medium-rise steel structure, a shear tab can't be applied for supporting shear force because of geometrical limitation. So it is required to propose details of improved double split tee connection to support shear force as well as flexural force. This research was performed to see if enough rotational stiffness is found when the double split tee connection without shear tab which was obtained through analytic and experimental researches by Yang et al. is applied to a low- or medium-rise steel structure. Also, it was seen if the low- or medium-rise steel structure having double split tee connection without shear tab has safe structural behavior, as well as material saving effect.

• Journal of Korean Society of Steel Construction
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• v.23 no.2
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• pp.147-158
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• 2011

The purpose of this research was to analyze the connections of the seismic-performance values for domestic-performance-based designs. Basic research on the performance design method has been increasing of late, along with performance-based organization investigations. These investigations concern the performance level state of steel structure buildings. According to the performance limit state, seismic-performance values should be presented as appropriate steel structure engineering amounts. The first step, based on the full-scale steel structure experiments, involves researching on the making of a basic document. The moment-rotation angle relationship results of the experiment on the moment-frame connection were used to assort the functional and undamaged limits, which were assumed to be less than the yield moment. Moreover, the repairable and safety limits, which were assumed to exist between the yield and maximum moments, were assorted by investigating the accumulated plastic deformation ratio.

• Journal of Korean Society of Steel Construction
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• v.10 no.3 s.36
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• pp.553-564
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• 1998

Recently, more and more steel-deck structural system for two story roads has been adopted as a solution against traffic congestion in urban area, mainly because of fast construction, reduced self-weight, higher stiffness and efficient erection compared to that of concrete decks. The main objective is to study on the unit-elective optimal type and proportioning of a rational steel-deck system for two story roads using an optimum design program specifically developed for steel-deck systems. The objective function for the optimization is formulated as a minimum cost design problem. The behavior and design constraints are formulated based on the ASD(Allowable Stress Design) criteria of the Korean Bridge Design Code. The optimum design program developed in this study consists of two steps - the first step for the optimization of the steel box or plate girder viaducts, and the second step for the optimum design of the steel-decks with closed or open ribs. A grid model is used as a structural analysis model for the optimization of the main girder system, while the analysis of the deck system is based on the Pelican-Esslinger method. The SQP(Sequential Quadratic Programming) is used as the optimization technique for the constrained optimization problem. By using a set of application examples, the rational type related to the optimized steel-deck system designs is investigated by comparing the cost effectiveness of each type. Based on the results of the investigation it may be concluded that the optimal linear box girder and deck system with closed ribs may be utilized as one of the most rational and economical viaducts in the construction of two-story roads.

• Journal of Korean Society of Steel Construction
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• v.11 no.1 s.38
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• pp.1-11
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• 1999

The aim of this study is to construct a machine vision monitoring system for an automatic visual inspection of weld joint in steel structure. An image processing algorithm for a visual weld defects detection on weld bead is developed using the intensity image. An optic system for getting four intensity images was set as a fixed camera position and four different illumination directions. The input images were thresholded and segmented after a suitable preprocessing and the features of each region were defined and calculated. The features were used in the detection and the classification of the visual weld defects. It is confirmed that the developed algorithm can detect weld defects that could not be detected by previously developed techniques. The recognized results were evaluated and compared to expert inspectors' results.

• Journal of Korean Society of Steel Construction
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• v.9 no.2 s.31
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• pp.229-235
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• 1997

In order to check the influence of the randomness in yield strengths on the energy dissipation capacity of steel structures, behaviour factors applied for the "Response Spectrum Method" and their distributions are determined in this study with 7 steel framed models. Also 4 artificial accelerograms simulated with a given spectrum are applied to check the influence of the randomness in seismic action on the behviour factor. To execute numerous time-step calculations for the investigation a time-step analysis method is developed and applied after the reliability estimation to determine the action effects.