• Steel and Composite Structures
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• 제39권1호
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• pp.35-50
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• 2021

Eccentrically braced frames (EBFs) are utilized as a lateral resisting system in high seismic zones. Links are the primary source of energy dissipation and they are exposed to high deformation, which may lead to buckling. Web stiffeners were introduced to prevent buckling of shear link. AISC 341 provides the required vertical stiffeners for a shear link. In this study, different stiffener configurations were examined. The main objective is to improve the behavior of short links using different stiffener configurations. Pursuant to this goal, a comprehensive numerical study is conducted using ABAQUS. Shear links with different stiffener configurations were subjected to cyclic loading using loading protocol mandated by AISC 341. The results are compared in terms of energy dissipation and shear capacities and rupture index. The proposed stiffener configurations were further verified with different link length ratios, I-shapes and thickness of stiffener. Based on the results, the stiffener configuration with two vertical and two diagonal stiffeners perpendicular to each other is recommended. The proposed stiffener configuration can increase the shear capacity, energy dissipation capacity and the ratio of energy/weight up to 27%, 38% and 30%, respectively. Detailing of the proposed stiffener configuration is presented.

• 한국강구조학회 논문집
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• 제8권3호통권28호
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• pp.117-125
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• 1996

The stress patterns of vertical stiffener of plate girder bridge were examined by existing data of actual measurement stress for steel bridges and the structural details of vertical stiffener of plate girder bridge having seeked rationalization and abbreviation were investigated by 1/2 bridge model. As the results, the out-of-plane stress occur in the upper parts of vertical stiffner and fatigue cracks by the action of alternative stress is apt to occur in web plate of lower parts vertical stiffener. Also, the gap between lower parts of vertical stiffner and lower flange of plate girder bridge seeking rationalization and abbreviation is effective to adopt 100mm.

• 한국안전학회지
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• 제27권1호
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• pp.86-95
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• 2012

The BWIM(Bridge Weigh-In-Motion) is a technology to identify vehicle properties, such as weight, speed, axle spacing and running lane, passing over a bridge by using dynamic response of bridge member. Such information will be used for assessing durability and establishing a maintenance strategy of roadway structures. In this paper, as a first step for developing BWIM system, analytical and experimental studies were conducted in order to verify whether the response of vertical stiffener in steel girder bridge can be used to identify vehicle properties running on the bridge. It was known from this study that such vehicle information could be estimated reasonably by using strain time history curve of a vertical stiffener due to running vehicles. It is because the effect of each axle-load of vehicle appears definitely in the curve. However, as the magnitude of strain of vertical stiffener is effected by running pattern of vehicles, further study is necessary to reduce error when estimating vehicle weight.

• 한국강구조학회 논문집
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• 제9권1호통권30호
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• pp.37-49
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• 1997

The buckling behavior of the web of steel girders are largely dependent on the size and the location of stiffeners and the restraining effect of top and bottom flanges. Elastic and inelastic buckling analyses based or the Spline Finite Strip Method were executed to study the stiffening effect of the longitudinal stiffener on the web of box girders and to find how the top and bottom flanges had effects on the web, where geometric boundary conditions were limited by both hinged, both fixed and the flange sections. The basic assumption for the longitudinal end boundary conditions was that the vertical stiffeners had the rigidity enough to force nil deflection line on the web panel so that the junction line between web and vertical stiffener was assumed to be hinged boundary conditions. The provisions on the longitudinal stiffener of the plate and box girders of the Korean Standard Highway Bridge Specifications(1995) and AASHTO Specifications(1994 LRFD) were compared with the results obtained numerically for the various longitudinal stiffener size of box girders. Simple equations and design curves for the longitudinal stiffener of the web were proposed for the practical use.

• 한국공간구조학회논문집
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• 제4권4호
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• pp.137-144
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• 2004

Recently, as steel structures become higher and more long-spanned, application of high-strength steels is increasing gradually. However, criteria and example for design of high-strength steel are not built up. exiting criteria for structural steels is not proper for economical design of high-strength steel. Moreover, exiting criteria will be decrease the fatigue performance of steel bridge using high-strength steel. Therefore, criterion for application of high-strength steel must be established. In this paper, the behavior of plate girder using high-strength vertical stiffeners was clarified by carrying out layer elastic-plastic finite element analysis using finite deformation theory. In order to optimize the design and construction of plate girder using high-strength vertical stiffener, criterion for application of high-strength vertical stiffener is proposed.

• 대한안전경영과학회지
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• 제25권2호
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• pp.187-192
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• 2023

In piping systems, trapeze hangers are subjected to vertical and horizontal seismic loads and stiffeners are used. In this study, monotonic compression tests were conducted with the removable stiffeners using three variables: stiffener clamp fixing position, section length, and installation direction. The maximum load reinforced with stiffeners could withstand a compressive load of 11kN by applying a safety factor of 10%. It could be estimated that the fixing clamp spacing or the length of shape and load had a proportional relationship. And the stiffener must be fixed in the direction of the strong axis on hinge parts. Also the stiffener buckiling load design proposes to use a method of calculate the flexural buckling compressive strength of and unreinforced full threaded bolt.

• 한국강구조학회 논문집
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• 제15권6호통권67호
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• pp.701-709
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• 2003

이 논문은 모멘트 저항골조의 접합부에 이용하기 위한 T-스티프너로 보강된 접합부의 내진성능에 관해 나타냈다. 접합부는 보플랜지와 기둥플랜지에 T-스티프너의 수평 및 수직요소가 용접되어 보강되었다. T-스티프너 접합부의 거동을 명확히 파악하기 위해 유한요소해석과 실험이 수행되었다. 유한요소해석결과, T-스티프너의 수평요소의 길이가 길어짐에 따라 T-스티프너는 보플랜지와 수평요소사이의 응력집중을 줄이는데 효과적임을 나타냈다. 또한, 접합부의 이력 거동을 파악하기 위해 실대형 접합부 실험을 실시하였다. 주요 변수는 보에 대한 T-스티프너의 강도비와 수평요소의 형상이다. 수평요소의 길이가 길수록 접합부의 변형능력은 증가하였고, 모든 실험체는 방추형의 안정된 이력거동을 나타내었다.

• 한국강구조학회 논문집
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• 제21권1호
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• pp.93-103
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• 2009

2거더 플레이트교는 주부재인 바닥판과 거더, 2차부재인 가로보, 수직보강재 및 수평보강재 등으로 구성되어 있다. 2거더교는 AASHTO와 국내의 도로교설계기준에는 하나의 거더가 손상되면 그 교량의 기능과 안전성에 문제가 야기되는 단재하 경로 구조로 규정되어 있다. 이러한 이유 때문에 2거더교의 피로균열은 교량의 안전성에 심각한 영향을 줄 수 있다. 따라서 본 논문에서는 2거더교에서 피로균열 발생 가능성이 높은 수직보강재와 거더 복부의 연결부를 대상으로 수직보강재 스캘럽 곡률반경 및 복부두께를 변화시키면서 피로 평가를 수행하였다. 이 결과에 기초하여 피로에 유리한 구조상세 및 간이 평가식을 제안하였다.

• Steel and Composite Structures
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• 제12권1호
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• pp.13-29
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• 2012

This paper is an experimental study on the behavior of vertical shear link in normal (steel section with and without stiffener) and composite (steel section with concrete located at the area limited to web and flanges of the section) configurations. This study is mainly aimed to perceive failure mechanism, collect laboratory data, and consider the effect of number of transverse reinforcements on strength and ductility of composite vertical links. There have been four specimens selected for examining the effects of different details. The first specimen was an I section with no stiffener, the second composed of I section with stiffeners provided according to AISC 2005. The third and fourth specimens were composed of I sections with reinforced concrete located at the area between its flanges and web. The tests carried out were of quasi-static type and conducted on full scale specimens. Experimental findings show remarkable increase in shear capacity and ductility of the composite links as compared to the normal specimens.

• 한국강구조학회 논문집
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• 제23권4호
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• pp.455-464
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• 2011

본 논문에서는 곡선 보강 복부판의 좌굴해석을 대체전단변형률 장을 갖는 8, 9절점 평면 쉘요소를 이용한 유한요소해석을 통하여 수행하였다. 수평보강재 및 수직보강재를 갖는 경우의 수직면내 곡선 복부판의 좌굴거동을 조사하기 위해 면내 모멘트 하중을 받는 경우에 대해서 복부판의 폭(b)의 변화, 보강재와 복부판의 휨-강성비(${\gamma}=EI/bD$)의 변화에 대한 변수연구를 수행하였다. 보강재를 갖지 않는 경우의 수직면내 곡선 복부판의 정적거동에 대해서도 조사되었다. 또한 모멘트 하중을 받는 경우에서 수평 보강재 및 수직 보강재의 좌굴능력이 비교 되었다.