• 한국철도학회:학술대회논문집
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• 한국철도학회 2005년도 춘계학술대회 논문집
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• pp.712-717
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• 2005

When the weight if a concrete member makes problems, or when the cost of the concrete is relatively high, it may be economical to use a hollow concrete member. But a hollow R.C column may have poor ductility because of the brittle failure at the inner face of the hollow R.C column. This brittle failure results from the absence of the confinement at the inner face of the hollow R.C column. To avoid this brittle failure an internally confined hollow R.C column by a steel tube was developed before. In this study, a hollow R.C column is internally confined by a corrugated steel tube instead of a general flat steel tube. And a column ductility is performed. Test results show that the energy ductility ratio of a internally confined hollow R.C column by a by a corrugated steel tube corresponds to $80\%$ of the energy ductility ratio of a general solid R.C column.

• Steel and Composite Structures
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• 제7권4호
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• pp.321-337
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• 2007

The investigation on the behaviour of cold-formed stainless steel non-slender circular hollow section columns is presented in this paper. The normal strength austenitic stainless steel type 304 and the high strength duplex materials (austenitic-ferritic approximately equivalent to EN 1.4462 and UNS S31803) were considered in this study. The finite element method has been used to carry out the investigation. The columns were compressed between fixed ends at different column lengths. The geometric and material nonlinearities have been included in the finite element analysis. The column strengths and failure modes were predicted. An extensive parametric study was carried out to study the effects of normal and high strength materials on cold-formed stainless steel non-slender circular hollow section columns. The column strengths predicted from the finite element analysis were compared with the design strengths calculated using the American Specification, Australian/New Zealand Standard and European Code for cold-formed stainless steel structures. The numerical results showed that the design rules specified in the American, Australian/New Zealand and European specifications are generally unconservative for the cold-formed stainless steel non-slender circular hollow section columns of normal and high strength materials, except for the short columns and some of the high strength stainless steel columns. Therefore, different values of the imperfection factor and limiting slenderness in the European Code design rules were proposed for cold-formed stainless steel non-slender circular hollow section columns.

• Steel and Composite Structures
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• 제6권4호
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• pp.285-302
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• 2006

This paper describes the design and behaviour of cold-formed stainless steel slender circular hollow section columns. The columns were compressed between fixed ends at different column lengths. The investigation focused on large diameter-to-plate thickness (D/t) ratio ranged from 100 to 200. An accurate finite element model has been developed. The initial local and overall geometric imperfections have been included in the finite element model. The material nonlinearity of the cold-formed stainless steel sections was incorporated in the model. The column strengths, load-shortening curves as well as failure modes were predicted using the finite element model. The nonlinear finite element model was verified against test results. An extensive parametric study was carried out to study the effects of cross-section geometries on the strength and behaviour of stainless steel slender circular hollow section columns with large D/t ratio. The column strengths predicted from the parametric study were compared with the design strengths calculated using the American Specification, Australian/New Zealand Standard and European Code for cold-formed stainless steel structures. It is shown that the design strengths obtained using the Australian/New Zealand and European specifications are generally unconservative for the cold-formed stainless steel slender circular hollow section columns, while the American Specification is generally quite conservative. Therefore, design equation was proposed in this study.

• Steel and Composite Structures
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• 제6권1호
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• pp.71-85
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• 2006

This paper presents the results of a series of tests carried out on cold-formed steel rectangular hollow and concrete infilled beam to column connections and frames. A stub column was chosen such that overall buckling does not influence the connection behaviour. The beam chosen was a short-span cantilever with a concentrated load applied at the free end. The beam was connected to the columns along the strong and weak axes of columns and these connections were tested to failure. Twelve experiments were conducted on cold-formed steel direct welded tubular beam to column connections and twelve experiments on connections with concrete infilled column subjected to monotonic loading. In all the experiments conducted, the stiffness of the connection, the ductility characteristics and the moment rotation behaviour were studied. The dominant mode of failure in hollow section connections was chord face yielding and not weld failure. Provision of concrete infill increases the stiffness and the ultimate moment carrying capacity substantially, irrespective of the axis of loading of the column. Weld failure and bearing failure due to transverse compression occurred in connections with concrete infilled columns. Six single-bay two storied frames both with and without concrete infill, and columns loaded along the major and minor axes were tested to failure. Concentrated load was applied at the midspan of first floor beam. The change in behaviour of the frame due to provision of infill in the column and in the entire frame was compared with hollow frames. Failure of the weld at the junction of the beam occurred for frames with infilled columns. Design expressions are suggested for the yielding of the column face in hollow sections and bearing failure in infilled columns which closely predicted the experimental failure loads.

• Steel and Composite Structures
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• 제20권6호
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• pp.1259-1274
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• 2016

A precast composite column system has been developed in this study by utilizing multi interlocking spiral steel into a centrifugally-formed hollow-core precast (CHPC) column. The proposed hybrid column system can have enhanced performances in the composite interaction behavior between the hollowed precast column and cast-in-place (CIP) core-filled concrete, the lap splice performance of bundled bars, and the confining effect of concrete. In the experimental program, reversed cyclic loading tests were conducted on a conventional reinforced concrete (RC) column fabricated monolithically, two CHPC columns filled with CIP concrete, and two steel-reinforced concrete (SRC) columns. It was confirmed that the interlocking spirals was very effective to enhance the structural performance of the CHPC column, and all the hollow-core precast column specimens tested in this study showed good seismic performances comparable to the monolithic control specimen.

• 한국강구조학회 논문집
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• 제17권2호통권75호
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• pp.207-216
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• 2005

본 논문은 스테인리스 각형강관 및 원형강관에 대한 좌굴내력에 관한 연구로서 건축구조용 강재로서의 적용성 검토를 위해, 세장비를 주요 변수로 한 소재의 인장강도실험과 stub-column의 압축강도실험, 기둥의 중심압축실험을 실시하여 강재의 기계적 성질과 기둥의 강도 및 거동을 파악한다. 또한 이론해석과 각국 기준식(AIK-LSD, AISC-LRFD, AIJ-LSD, SIJ-ASD) 및 복수강도곡선의 적용을 통한 이론값과 실험값을 비교함으로서 건축구조용 강재로서 적용성 검토와 구조설계기준 확립을 위한 기초 자료를 구하는데 목적이 있다.

• 한국방재학회 논문집
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• 제7권3호
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• pp.1-7
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• 2007

중공 RC 기둥은 중실 RC 기둥에 비해 자중의 감소 및 재료 절감에 대한 장점을 가진다. 그러나 중공 RC 기둥은 안쪽면의 취성파괴로 인하여 낮은 연성 거동을 할 가능성이 있다. 이러한 문제점을 해결하기 위해 중공 부재 내의 콘크리트 3축 구속 상태로 존재하게 하는 강관으로 보강된 중공 RC 기둥이 개발되었으며, 본 연구에서는 강관으로 보강된 중공 RC 기둥의 중공비를 $0.50{\sim}0.85$까지 변화 시켜 중공비에 따른 작용하중에 대한 안전율, 연성도, 재료비, 교각 총 중량에 대한 거동 특성을 파악하였다.

• 대한토목학회논문집
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• 제26권4A호
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• pp.565-575
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• 2006

구속된 콘크리트는 구속되지 않은 콘크리트에 비해 상당히 큰 강도를 갖는다. 따라서 콘크리트의 구속응력을 증가시키는 것은 강도의 증가를 유도할 수 있다. 하지만 중공교각의 경우, 심부구속력의 부재로 인하여 중공교각의 안쪽면에서 취성파괴가 발생하며, 이는 기둥의 강도 저하 및 연성의 저하를 초래한다. 이러한 문제를 극복하기 위하여, 강관 삽입 중공 RC(Reinforced Concrete) 기둥이 개발되었으며, 본 연구에서는 실험을 통하여 삽입 강관에 의한 내부 구속력의 효과를 검증하였다. 총 36개의 시험체를 제작하여 실험을 수행하였으며, 실험 결과를 통하여 삽입 강관의 구속력과 이로 인한 콘크리트의 강도 증가를 확인하였다.

• 한국방재학회 논문집
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• 제8권2호
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• pp.31-38
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• 2008

파형강관으로 내부 구속된 중공 철근콘크리트 기둥(파형강관 내부 구속 중공 RC 기둥, ICH RC-CT column ; Internally Confined Hollow RC column with a Corrugated Steel Tube)의 내진 성능 평가 실험을 수행하였다. 준정적 실험을 통하여 ICH RC-CT 기둥과 일반 중실 RC 기둥의 내진 성능을 비교 평가 하였다. 각각의 기둥 시험체에 대해 하중과 변위의 관계를 측정하였으며, 이를 바탕으로 연성도, 소산에너지, 등가 감쇠비, 손상 지수가 계산되었다. 실험 결과 ICH RC-CT 기둥은 중실 RC 기둥에 비해 작은 에너지 소산능력을 보여주었으나, 에너지 연성도와 등가 점성 감쇠비 측면에서는 거의 대등한 성능을 보여주었다.

• 한국지진공학회논문집
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• 제21권1호
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• pp.21-29
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• 2017

Purpose of this study is to investigate structural behavior of the rectangular hollow column with various transverse reinforcement details. Experimental variables are diameter, arrangement details and lateral spacing of cross tie. A total of 66 column specimens have been prepared and tested under axial compressive load. Test results showed that behaviors of column specimens were different depending on the cross tie details. Specimens with cross tie wrapping longitudinal steel and transverse steel have greater strength and ductility than specimens with cross tie wrapping the longitudinal steel.