• Journal of the Computational Structural Engineering Institute of Korea
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• v.18 no.4 s.70
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• pp.417-426
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• 2005

Recent days composite bridge dock is gaining attraction due to many advantages such as light weight, high strength, corrosion resistance, and high durability. In this study, composite deck models of hat, box and triangular section type wore fabricated with VARTM Process. For these models, three point flexural tests wore carried out both in strong and weak axis. The experimental results were compared with each other to determine efficient section profile. It has been demonstrated that composite sandwich deck has strong potentials to be used as bridge deck in the new construction and rehabilitation works.

• Journal of Korean Society of Steel Construction
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• v.16 no.2 s.69
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• pp.275-284
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• 2004

The behavior of the connection for beam-to-column weak axis connection and its details should be identified. Thus, each element is considered a panel zone, and the horizontal stiffener's presence or absence and position in bracket-type welding connection are used as variables to compare the behavior of strong axis connection and weak axis connection. In this study, the strength of connection is calculated by substituting the simple beam-strengthened vertical stiffeners for connection in the presence of horizontal stiffeners. In the absence of horizontal stiffeners, the strength of connection can be calculated using local flange bending strength considering local web yielding strength, web crippling, and web buckling strength. The results of the theoretical analysis and experiments are compared.

• Journal of the Korean Wood Science and Technology
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• v.46 no.5
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• pp.425-436
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• 2018

This study was conducted to evaluate the planar (rolling) shear strength of OSB (oriented strand board) panels and domestic plywood through 5 point bending test method in ASTM D2718 standard. The test specimens were prepared in parallel and perpendicular direction to major axis (along the length of panels) and tested up to failure, and failure modes were also examined. From the test results, rolling shear strength were found to be $1.32{\sim}1.94N/mm^2$ in parallel to major axis, and $1.46{\sim}1.99N/mm^2$ in perpendicular to major axis respectively. Little difference was found between parallel and perpendicular direction of rolling shear strength. There were no statistically significant differences in rolling shear strength between Canadian OSB and domestic plywood in the parallel direction, and between Chilean OSB and domestic plywood in the perpendicular direction. The shear failure was observed in all tested OSB panels, whereas shear failure, glue line delamination, and bending combined with shear failure were observed in the domestic plywood.

• Journal of the Korea institute for structural maintenance and inspection
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• v.18 no.3
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• pp.58-68
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• 2014

Transverse steel bars are used in the plastic hinge zone of columns to insure adequate confinement, prevention of longitudinal bar buckling and ductile behavior. Fabrication and placement of rectangular hoops and cross-ties in columns are difficult to construct and require larger amount of transverse steels. In this paper, to solve these problems, the new lateral confinement method using oblong hoop is proposed for the transverse confinement of columns of the oblong cross-section and flared column. The experimental study for octagonal oblong cross-section was carried out by the flared columns test in strong axis. The lateral confinement method using proposed oblong hoop detail showed satisfactory performance of lateral confinement. Therefore it can be the alternative for oblong cross-section and flared column with improved workability and cost-efficiency.

• Journal of the Korea institute for structural maintenance and inspection
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• v.12 no.4
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• pp.71-78
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• 2008

In the case of the railway bridges, uplift forces were occurred at the edge of the segments when vehicular loads were applied. These forces caused the compressive and tensile forces in the fastening system. In the past, a structural analysis has been performed to investigate the safety of fastening system which was modeled with one directional spring elements based on the compressive test of fastening system. In this case, the stiffness of the spring element was obtained from experimental study which was conducted by compressive load. Therefore, to perform rational and exact structural analysis, the translational stiffness of the fastening system obtained from the experimental study applied the tensile load and the rotational stiffness should be considered because it was occurred the tensile force as well as the compressive force in fastening system. In this study, an elastic and inelastic experimental study was performed for six specimens. The translational stiffness along the vertical axis of rail and the rotational stiffness along the strong axis of rail were investigated, also structural behavior of the fastening system was analyzed.

• Magazine of the Korea Concrete Institute
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• v.14 no.6
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• pp.88-95
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• 2002

최근 국내에 60층을 초과하는 초고층 구조물들이 많이 건설되고 있으며, 콘크리트 품질의 향상 특히 콘크리트의 고강도화에 힘입어 이를 이용한 철근 콘크리트 고층 구조물들이 증가하고 있다. 이에 따라 이들 초고층, 초대형 구조물을 지지할 수 있는 고축력, 고연성의 기둥에 대한 설계 및 시공이 요구되고 있으며, 이에 가장 적합한 구조요소라 할 수 있는 콘크리트 충전 강관기둥(Concrete Filled Steel Tube Columns : CFT Columns)의 설계 및 시공에 관심이 높아지고 있다. 이러한 콘크리트 충전 강관기둥은 콘크리트가 강관에 의해 둘러싸여지기 때문에 축하중 저항 능력이 증가되는 장점과 동일한 단면으로 H형강을 사용한 순수 철골조 H형강 기둥의 강축(strong axis)과 약축(weak axis) 문제해결과 동시에 강성 (stiffness)을 증가시킬 수 있으며, 내화 성능이 향상되고 거푸집 대체 재료로 사용되는 등 여러 가지 장점을 지니고 있다. 한편 충전 강관기둥에 작용하는 축하중은 대부분 콘크리트가 부담하게 되는데 이러한 충전강관 기둥의 장점을 극대화하기 위해서는 보통강도 콘크리트보다는 압축강도 및 탄성계수가 큰 고강도 콘크리트의 사용은 불가피하게 된다.(중략)

• Journal of Korean Association for Spatial Structures
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• v.4 no.1 s.11
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• pp.87-95
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• 2004

This paper shows the study on the capacity of H-shape column at elevated temperature in fire. The main parameters are temperatures, slenderness ratios and load ratios. The physical properties of steel material at elevated temperatures are according to EC3 Part 1.2. The critical temperature of local buckling at elevated temperatures are lower when the yield strength of the material is higher, and when the ratios of width-thickness of plates are larger. The evaluation capacity of uniformly heated steel cloumns were considered to axial forces, moments of strong axis and weak axis to the LRFD.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2010.04a
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• pp.18-21
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• 2010

현재 유전개발이 가속화 되고 있는 캐나다의 유전개발현장에서 진입도로용으로 사용하고 있는 목재 가도 매트를 대체하기 위해 고강도 경량 고내구성 특성을 갖는 복합소재 리그매트를 개발하였다. 기존에 본 연구진이 개발한 리그매트는 중차량의 반복하중에 취약한 거동을 보였으므로 이를 해결하기 위한 개선형 리그매트를 개발하였다. 개선형 리그매트의 구조안전성을 평가하기 위하여 단일데크의 강축 휨에 대한 해석 및 시험을 실시하여 휨 거동 특성을 조사하였다.

• Journal of Korean Society of Steel Construction
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• v.27 no.6
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• pp.513-523
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• 2015

In steel moment frames constructed of H-shapes, strong-axis moment connections should be used for maximum structural efficiency if possible. And most of cyclic seismic testing, domestic and international, has been conducted for strong-axis moment connections and cyclic test data for weak-axis connections is quite limited. However, when perpendicular moment frames meet, weak-axis moment connections are also needed at the intersecting locations. Especially, both strong- and weak-axis moment connections have been frequently used in domestic practice. In this study, cyclic seismic performance of RBS (reduced beam section) weak-axis welded moment connections was experimentally investigated. Test specimens, designed according to the procedure proposed by Gilton and Uang (2002), performed well and developed an excellent plastic rotation capacity of 0.03 rad or higher, although a simplified sizing procedure for attaching the beam web to the shear plate in the form of C-shaped fillet weld was used. The test results of this study showed that the sharp corner of C-shaped fillet weld tends to be the origin of crack propagation due to stress concentration there and needs to be trimmed for the better weld shape. Different from strong-axis moment connections, due to the presence of weld access hole, a kind of CJP butt joint is formed between the beam flange and the horizontal continuity plate in weak-axis moment connections. When weld access hole is large, this butt joint can experience cyclic local buckling and subsequent low cycle fatigue fracture as observed in this testing program. Thus the size of web access hole at the butt joint should be minimized if possible. The recommended seismic detailing such as stickout, trimming, and thicker continuity plate for construction tolerance should be followed for design and fabrication of weak-axis welded moment connections.

• Journal of the Korea Concrete Institute
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• v.19 no.4
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• pp.401-409
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• 2007

The objective of this research is to provide better knowledge on the behavior of strong axis SRC column-RC beam joint, supported by experimental results, that can be broadly applicable to many structures. For this purpose, firstly literature reviews and field survey were made to classify the most commonly used for these types of joints. Then, experimental program was designed and performed including 6 SRC column-RC beam joint specimens designed with various joint details. Using the experimental results obtained from the quasi-static cyclic tests, structural performances of the joints such as hysteretic curves, maximum strength capacities, strength degradation beyond the maximum strength, ductilities, and energy dissipation capacities were investigated. Test results showed that specimens with wide beam shape (RCW-P, RCW-W, RCW-F) and T beam shape (RCT-W) showed better structural performances than the bracket type specimens (HBR-L, HBR-S). These specimens also revealed to have higher strength capacities than the nominal design strength. However, H beam bracket type specimens (HBR-L, HBR-S) need further study both analytically and experimentally to verify the reason for unexpected structural performances.