• 한국건설관리학회논문집
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• 제8권3호
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• pp.87-96
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• 2007

최근 국 내외 건설 환경은 대형화, 전문화, 다양화되고 있다. 이러한 건설 환경의 변화로 인하여 강구조물 프로젝트의 수요가 점차 증가하고 있으며 강구조물 공사의 효율적 품질관리의 중요성은 더욱 부각되고 있다. 강구조물 공사는 다수의 협력업체와 수많은 공종에 따른 많은 기술력을 요구하는 공사이기 때문에 다양한 리스크와 불확실 요인을 내포하고 있다. 하지만 현재 강구조물 공사의 리스크 대응 및 관리는 과학적이고 체계적 인 방법으로 진행되는 것 보다 공사자의 직감과 경험에 의존한 방법으로 진행되고 있다. 강구조물 공사의 리스크 요인을 파악하고 대응방안을 세우는 것은 강구조물 공사의 품질관리 성패를 좌우한다고 할 수 있다. 따라서 본 연구는 강구조물 공사의 과학적이고, 체계적인 리스크 관리를 위하여 전문가들의 설문조사를 실시하고 계층적 분석법(Analysis Hierarchy Process : 이하 AHP)을 통하여 리스크 중요도와 분석된 리스크 요인의 대응방안을 제시함으로써 강구조물 공사의 품질관리 체계를 정립하고자 한다.

• Journal of Korea Trade
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• 제25권4호
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• pp.1-16
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• 2021

Purpose - This study reviews changes in the steel export-import structure between Korea and Japan to strengthen the competitive advantage of the Korea Steel industry using a trade-related index. Design/methodology - This study focuses on analyzing comparative advantage based on the trade intensity index (TII), revealed comparative advantage index (RCA), and trade specialization index (TSI). Findings - Korea's steel import from Japan increased due to the domestic supply shortage of HR (Hot Rolled Coil) and Plate, rather than the sharp decline of the domestic steel industry's competitiveness in 2010. However, after the completion of Hyundai Steel's blast furnace, the Korea Steel industry solved the supply shortage. Additionally, the import of Japanese steel products had decreased significantly from 2009 to 2019. Originality/value - This study attempts to analyze Japanese steel products' competitiveness in trade and the domestic influence of high-quality Japanese steel products. These results are connected to domestic steel supply and demand structure and relations with the Japanese steel industry. After completing Hyundai Steel's blast furnace, the Korea Steel industry solved the supply shortage, and the import of Japanese steel products has decreased significantly from 2009 to 2019.

• 국제초고층학회논문집
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• 제8권3호
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• pp.161-167
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• 2019

Making full use of material strength, maintaining sufficient ductility of structural components, and ensuring simple and robust connections are crucial to the development of steel-concrete composite structures. The steel-tubed concrete structure uses thin-walled steel tube to provide confinement, so that the strength and ductility of the concrete core are improved. Meanwhile, the thin-walled steel tube is terminated at the beam-column joint to avoid the local buckling problem and simplify the connections between steel tube and RC members. A brief overview of the development of steel-tubed concrete structures is presented. Through the discussion on the structural behavior of steel-tubed concrete and the introduction of typical practical projects, the prospects for future research are highlighted.

• 한국강구조학회 논문집
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• 제25권1호
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• pp.71-80
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• 2013

구조, 시공 및 내화측면에서 우수한 콘크리트충전강관(CFT)부재에 대해서 구성재료의 강도가 높은 경우 즉, 콘크리트 압축강도가 100MPa 이상이면서 강관의 항복강도가 650MPa 이상인 경우에 대한 내화성능 평가실험 및 해석적 연구는 미비한 실정이다. 본 연구에서는 이러한 부재에 대해서 내화성능 거동을 파악하고자 ${\Box}-400{\times}400{\times}15$, 부재길이 3,000mm인 실물대 중심재하 내화실험을 행하였다. 실험변수는 중심축력을 5,000kN과 2,500kN로 하였다. 실험결과, 고강도 콘크리트의 폭렬 및 콘크리트 내부 균열에 의하여 축하중이 클수록 조기에 내력을 상실하였다. 또한, 유한차분법과 변형률적합조건을 이용한 비정상온도해석 및 응력해석을 수행하였으며, 고강도 재료모델은 Eurocode모델을 이용하였다. 해석모델은 시간-축변위 관계를 합리적으로 예측할 수 있었다.

• 한국강구조학회 논문집
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• 제16권3호통권70호
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• pp.377-385
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• 2004

본 논문에서는 강판-콘크리트 벽체구조에 부착되는 기기를 지지하기 위하여 설치되는 지지대와 벽채와의 접합 성능을 파악하기 위하여 구조실험 및 유한요소해석을 수행하였다. 구조실험은 9개의 시험체를 제작하여 파괴모드 및 최대내력을 파악하였으며 유한요소해석모델을 작성하여 이를 실험결과와 비교 검증한 후 강판두께, 스터드 볼트 간격, 지지대의 위치 및 크기 등의 영향인자가 벽체 접합부의 거동 및 내력에 미치는 변화를 살펴보았다. 해석 시험체의 하중-변형의 관계로부터 시험체의 항복내력 및 최대내력을 정의 하였으며 향후 항복선 해석을 위한 토대를 마련하였다.

• 한국강구조학회 논문집
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• 제22권5호
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• pp.455-463
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• 2010

본 연구는 철근콘크리트 구조와 강판 콘크리트 구조가 혼합되어 이질접합부가 있는 보형 구조물의 역학적 특성을 평가하기 위하여 수행하였다. 강판콘크리트 구조는 현재 국내와 일본, 미국 등에서 연구가 진행되고 있고, 대규모 산업설비에서 철근콘크리트 구조의 대안으로 실험연구가 수행되고 있다. 본 연구에서는 대규모 철근콘크리트 구조물에 강판 콘크리트 구조를 적용할 경우를 가정하여 보 형태의 구조물에 강판 콘크리트 구조와 철근 콘크리트 구조를 적용하여 이질접합부를 만들고, 면외하중을 파괴 시까지 가력하여 이질접합부를 가진 보형실험체의 휨 내력 및 구조특성을 평가하기 위하여 실험연구를 수행하였다.

• Steel and Composite Structures
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• 제27권1호
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• pp.123-133
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• 2018

Steel-concrete-steel (SCS) sandwich composite structure with corrugated-strip connectors (CSC) has the potential to be used in buildings and offshore structures. In this structure, CSCs are used to bond steel face plates and concrete. To overcome executive problems, in the proposed system by the authors, shear connectors are one end welded as double skin composites. Hence, this system double skin with corrugated-strip connectors (DSCS) is named. In this paper, finite element model (FEM) of push-out test was presented for the basic component of DSCS. ABAQUS/Explicit solver in ABAQUS was used due to the geometrical complexity of the model, especially in the interaction of the shear connectors with concrete. In order that the explicit analysis has a quasi-static behavior with a proper approximation, the kinetic energy (ALLKE) did not exceed 5% to 10% of the internal energy (ALLIE) using mass-scaling. The FE analysis (FEA) was validated against those from the push-out tests in the previous work of the authors published in this journal. By comparing load-slip curves and failure modes, FEMs with suitable analysis speed were consistent with test results.

• Corrosion Science and Technology
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• 제9권6호
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• pp.233-238
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• 2010

Hot-dipped Al-Mg-Si coatings to alternate Zn and Zn alloy coatings for steel were examined on metallographic structure, corrosion resistance, sacrificial ability, formation and growth of inter-metallic compounds, and mechanical properties. Near the eutectic composition of quasi-binary system of Al-$Mg_2Si$, very fine eutectic structure of ${\alpha}$-Al and $Mg_2Si$ was obtained and it showed excellent corrosion resistivity and sacrificial ability for a steel in sodium chloride solutions. Formation and growth of Al-Fe inter-metallic compounds at the interface of substrate steel and coated layer was suppressed by addition of Si. The inter-metallic compounds layer was usually brittle, however, the coating layer did not peel off as long as the thickness of the inter-metallic compounds layer was small enough. During sacrificial protection of a steel, amount of hydrogen into the steel was more than ten times smaller than that of Zn coated steel, suggesting to prevent hydrogen embrittlement. Al-Mg-Si coating is expected to apply for several kinds of high strength steels.

• Steel and Composite Structures
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• 제22권6호
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• pp.1217-1238
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• 2016

Mega composite structure systems have been widely used in high rise buildings in China. Compared to other structures, this type of composite structure systems has a larger cross-section with less weight. Concrete filled steel tubular (CFST) laced column to box-beam connections are gaining popularity, in particular for the mega composite structure system in high rise buildings. To enable a better understanding of the destruction characteristics and aseismic performance of these connections, three different connection types of specimens including single-limb bracing, cross bracing and diaphragms for core area of connections were tested under low cyclic and reciprocating loading. Hysteresis curves and skeleton curves were obtained from cyclic loading tests under axial loading. Based on these tested curves, a new trilinear hysteretic restoring force model considering rigidity degradation is proposed for CFST laced column to box-beam connections in a mega composite structure system, including a trilinear skeleton model based on calculation, law of stiffness degradation and hysteresis rules. The trilinear hysteretic restoring force model is compared with the experimental results. The experimental data shows that the new hysteretic restoring force model tallies with the test curves well and can be referenced for elastic-plastic seismic analysis of CFST laced column to composite box-beam connection in a mega composite structure system.

• 한국지진공학회논문집
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• 제25권4호
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• pp.153-160
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• 2021

The connection of the steel structure serves to transmit external forces to the main components. The same is true for the behavior of modular systems composed mainly of steel or composite members. In this study, the joint performance of the composite and steel modules proposed was evaluated. The analytical models of the two joint types were constructed and were subjected to cyclic loading to assess the safety and the energy dissipation capacity of the joint types. The analysis results of the joints showed that the joints of the modular systems remain stable when the joint rotation reached the seismic performance limit state of the 0.02 rad required for steel intermediate moment frame. It was also observed that the joint of the composite modular system showed higher energy dissipation capacity compared with the steel modular system.