• 대한기계학회논문집A
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• 제35권11호
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• pp.1515-1520
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• 2011

본 연구는 유한요소해석에 의해 300톤 골리앗 크레인의 구조해석 및 평가를 하였다. 300톤 골리앗 크레인의 구조는 110m의 스판과 50m의 높이로 구성되어 있다. 크레인은 자중, 크레인의 주행 관성력, 트롤리의 주행 관성력, 풍하중, 지진하중을 받는다. 다양한 하중 조건을 입력하여 크레인의 구조 해석을 수행하였다. 크레인의 등가응력과 전체 변형량을 ANSYS Workbench에서 얻은 결과를 이용하여 크레인의 구조 안전성 여부를 판단하였다.

• Structural Engineering and Mechanics
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• 제46권4호
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• pp.571-594
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• 2013

Railway truss bridges are amongst the essential structures in railway transportation. Minimization of the construction and maintenance costs of these trusses can effectively reduce investments in railway industries. In case of railway bridges, due to high ratio of the live load to the dead load, the moving load has considerable influence on the bridge dynamics. In this paper, optimization of the railway truss bridges under moving load is taken into consideration. The appropriate algorithm namely Hyper-sphere algorithm is used for this multifaceted problem. Through optimization the efficiency of the method successfully raised about 5 percent, compared with similar algorithms. The proposed optimization carried out on several typical railway trusses. The influences of buckling, deformation constraints, and the optimum height of each type of truss, assessed using a simple approximation method.

• 한국강구조학회 논문집
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• 제20권1호
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• pp.9-20
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• 2008

강박스거더교 다이아프램부에 있어서 경제적이고 합리적인 설계가 요망되어 진다. 본 연구에서는 시공중인 4경간 강박스거더교에서 콘크리트 상판 타설 시와 차량재하 시에 응력을 측정한다. 측정 결과는 지점부 다이아프램부와 중앙부에서 응력분배를 연구하기 위하여 분석된다. 다이아프램부 수직보강재의 높이별 응력과 이와 같은 높이의 다이아프램부 응력을 정리하고, 이들 결과를 분석하여 적정 수직보강재 길이의 효율성을 판단한다. 또한 다이아프램부 3조의 수직보강재 각각의 응력을 분석하고, 콘크리트 경화 후 차량 재하 시와 시에 따른 응력비를 산출하여 다이아프램부 설계합리화 연구의 기본 자료로 수립하고자 한다.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2008년도 정기총회 및 학술발표대회
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• pp.333-336
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• 2008

U-Channel Bridge is effective bridge type, because its edge beam performs role of barrier and enables to reduce additional dead loads. Nevertheless, there is possibility of bridge collapse under impact load due to car crash. Also, edge beam must have ability to induce safe driving and prevent falling accidents. Therefore, this study carries out analysis of behavior of edge beam and slab and evaluation of structural stability under impact loads, based on Korean Highway Bridge Design Specifications and AASHTO LRFD Bridge Design Specification. According to analysis result, the maximum stress of edge beam and slab satisfies specification of allowable stress.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2001년도 춘계학술대회 논문집
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• pp.639-642
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• 2001

The possibility of weight reduction of rotor part in gas-gas geater(GGH) is studied from the viewpoint of allowable stress. In this work, finite element analysis(FEA) is performed with original model and three weight-reduced models with different diaphragm thickness, respectively. Stress concentrations at rotor diaphragm happen due to the dead weight, pressure difference between treated gas and untreated gas and thermal distribution in the rotor. As the thickness of diaphragm is decreased, the stress level is increased. The direction of treated gas and untreated gas flow may affect the stress level. Fatigue life assessment is not considered because pressure difference, the only cyclic load, can be ignored. The possible weight-reduced model is presented.

• Wind and Structures
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• 제22권6호
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• pp.685-701
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• 2016

Downbursts are of great harm to transmission lines and many towers can even be destroyed. The downburst wind field model by Chen and Letchford was applied, and the wind loads of two typical transmission towers in inland areas and littoral areas were calculated separately. Spatial finite element models of the transmission towers were established by elastic beam and link elements. The wind loads as well as the dead loads of conductors and insulators were simplified and applied on the suspension points by concentrated form. Structural analysis on two typical transmission towers under normal wind and downburst was completed. The bearing characteristics and the failure modes of the transmission towers under downburst were determined. The failure state of tower members can be judged by the calculated stress ratios. It shows that stress states of the tower members were mainly controlled by 45 degree wind load. For the inland areas with low deign wind velocity, though the structural height is not in the highest wind velocity zone of downburst, the wind load under downburst is much higher than that under normal wind. The main members above the transverse separator of the legs will be firstly destroyed. For the littoral areas with high deign wind velocity, the wind load under downburst is lower than under normal wind. Transmission towers are not controlled by the wind loads from downbursts in design process.

• Nuclear Engineering and Technology
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• 제33권6호
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• pp.566-584
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• 2001

In this paper, the progressive deformation and the creep-fatigue damage for the conceptually designed reactor internals of KALIMER(Korea Advanced Liquid MEtal Reactor) are carried out by using the elastic analysis method in the RCC-MR code for normal operating conditions including the thermal load, seismic load (OBE) and dead weight. The maximum operating temperature of this reactor is 53$0^{\circ}C$ and the total service lifetime is 30 years. Thus, the time- dependent creep and stress-rupture effects become quite important in the structural design. The effects of the thermal induced membrane stress on the creep-fatigue damage are investigated with the risk of the elastic follow-up. To calculate the thermal stress, detailed thermal analyses considering conduction, convection and radiation heat transfer mechanisms are carried out with the ANSYS program. Using the results of the elastic analysis, the progressive deformation and creep-fatigue damages are calculated step by step using the RCC-MR in detail. This paper ill be a very useful guide for an actual application of the high temperature structural design of the nuclear power plant accounting for the time-dependent creep and stress-rupture effects.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2014년도 춘계 학술논문 발표대회
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• pp.16-17
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• 2014

The curtain wall construction applied on high-rise building facades in Korea became generalized, but specialty of the CMr(Construction Manager) who needs to perform economical project management with specialty in the curtain wall construction is still lacking. Therefore, this study analyzed the structure design standard of the curtain wall, researched economical design alternatives. Based on the research results, if the ratio of dead load against wind load is less than 0.1256, LRFD will be more economical.

• Structural Engineering and Mechanics
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• 제50권4호
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• pp.419-439
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• 2014

In this study, the structural performance of a seven span masonry arch bridge was evaluated. Investigations were performed on Aspendos (Belkis) Masonry Arch Bridge which was located on road of Aspendos Acropolis City in Antalya, Turkey. The old bridge was constructed in the early of fourth century AD, but it was exposed to the earthquakes in this region and the overloading by the river water. The old bridge was severely damaged and collapsed by probably an earthquake many years ago and a new bridge was then reconstructed on the remains of this old bridge by Seljuk in the 13th century. The bridge has also been affected from overflowing especially in the spring of each year, so some protective measures should be taken for this monumental bridge. Therefore, the structural performance under these loading has to be known. For this purpose, an initial finite element model was developed for the bridge and it was calibrated according to ambient vibration test results. After that, it was analyzed for different load cases such as dead, live, earthquake and overflow. Three load combinations were taken into account by deriving from these load cases. The displacements and the stresses for these combination cases were attained and compared with each other. The structural performance of Aspendos Masonry Arch Bridge was determined by considering the demand-capacity ratio for the tensile stress of the mortar used in Aspendos Masonry Arch Bridge. After these investigations, some concluding remarks and offers were presented at the end of this study.

• 한국공간구조학회논문집
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• 제3권3호
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• pp.105-110
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• 2003

This paper is presented an experimental studies on bond stress between steel and concrete in concrete filled Rectangular steel tubes. In the actual building frames, vertical dead and live loads on beams are usually transferred to columns by beam-to-column connections. In case when concrete filled steel tubes are used as columns of an actual building frame which has a simple connection, shear forces in the beam ends are not directly transferred to the concrete core but directly to the steel tube. Provided that the bond effect between steel tube and concrete core should not be expected, none of the end shear in the beams would be transferred to the concrete core but only to the steel tube. Therefore, it is important to investigate the bond strength between steel tube and concrete core in the absence of shear connectors.