• Transactions of the Korean Society of Mechanical Engineers A
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• v.35 no.11
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• pp.1515-1520
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• 2011

Structural analysis and evaluation for the 300ton Goliath Crane were conducted with an FEM tool. The Golliath Crane has a 300 ton hoisting weight, a 110 m span and a 50 m lift. All loads such as the self weight, crane traveling load, trolley traveling load, wind load, and earthquake force, etc., that are indicat in the reference standards, were inputted as various severe conditions affecting the crane. The deformation and equivalent stress (von Mises stress) were evaluated for the crane structures.

• Structural Engineering and Mechanics
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• v.46 no.4
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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.

• Journal of Korean Society of Steel Construction
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• v.20 no.1
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• pp.9-20
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• 2008

It is important to increase the economy and efficiency of the diaphragm of the steel box girder bridge design. In this study, an experimental test is performed in a 4-span steel box girder bridge, which was under constructed according to the dead load of slab concrete and vehicle load. The test result is analyzed to verify the stress distribution of the diaphragm and the middle span. Next, stresses on the vertical stiffener are analyzed according to height. Stresses on the diaphragm with equal height are arranged respectively. Also, the stress distribution of the diaphragm and the middle span. Next, stress on the vertical stiffeners are analyzed according to height. Stresses on the diaphragm with equal height are arranged respectively. Also, the vertical stiffeners in the diaphragm was studied, and using the analyzed results, the proper length of the ratio of vehicle load with curing concrete to vehicle load with asphalt is calculated in each part of the steel box girder bridge. The results provide data that serve as basis for an economical and efficient design for the steel box girder bridge diaphragm.

• 한국방재학회:학술대회논문집
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• 2008.02a
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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.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2001.04a
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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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• v.22 no.6
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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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• v.33 no.6
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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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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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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• v.50 no.4
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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.

• Journal of Korean Association for Spatial Structures
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• v.3 no.3 s.9
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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.