• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.77-82
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• 2002

Recently, adapt cases of concrete structure are increasing according to structural largeness and variety. We energetically continue to study empirical research about Steel Fiber but analytic research of Two-spans Beam With Steel Fiber to model real structure is just beginning stage. This study will suggest analytic algorithm of Two-spans Beam With Steel Fiber by comparing and analyzing deflection and strain of Two-spans Beam With Steel Fiber after we develop Nonlinear Analysis Program considering edge stress analysis.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2004.04a
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• pp.357-364
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• 2004

Recently, many high-rise apartment buildings using the box system composed of only reinforced connote walls and slabs, have been constructed In residential buildings such as apartments, vibrations occur from various sources and these vibrations transfer to neighboring residential units through walls and slabs. It is necessary to use a refined finite element model for an accurate vibration analysis of shear wall building structures. But it would take significant amount of computational time and memory if the entire building structure were subdivided into a finer mesh. Therefore an efficient analytical method, which has only translational DOFs perpendicular to walls or slabs by the matrix condensation technique, is proposed in this study to obtain accurate results in significantly reduced computational time.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2001.10a
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• pp.545-552
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• 2001

Analysis of a structure for vertical vibration requires a lot of computational efforts because large number of degrees of freedom are generally involved in the dynamic response. Especially, when a structure is loaded with local vibration source, it may not be economical to model the whole structure to obtain the responses of specific members located near or far from the sources. In this study, substructure models have been used for analysis of local vibration An analysis of local vibration is performed for the case that the loaded point and the response point are located on the same floor. Other analysis is performed for the case that the loaded point and the response point are located on the different floor. In this case, if only the floors on which loaded and response points are located are modeled, response of substructure model is very different from that of full model. So, there should be a consideration that degrees of freedom of floors in addition to those of loaded and response floors are included to improve results of dynamic analysis. In this study, floors between loaded floor and response floor were modeled so that modeshapes which affect the response are presented well.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2008.04a
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• pp.511-516
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• 2008

Recently, many researchers are studying a high-strength concrete, composite materials and composite structures to build structures more economic and stable all over the world. For instance, there is CFTA(Concrete Filled and Tied Steel Tubular Arch) girder that applies an arch structure and a pre-stressed structure to CFT(Concrete Filled Steel Tubular) Structure to maximize the efficiency of structure and economic. In this study, linear-elastic behavior analysis of CFTA gider filled with high-strength concrete was performed by using ABAQUS 6.5-1 and also the result was analyzed.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.597-602
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• 2006

Many researches have been studied several vibration control device such as TMD and TLD to reduce the influence of wind or seismic waves for high-rise buildings. TLD provides some advantages such as easy installation and low maintenance cost. However, because of the difficulties in evaluating the characteristics of TLD, the dynamic characteristics of TLD must be investigated by experiment or analysis. In this study, the dynamic response analysis of structure with TLD was carried out to verify the vibration control ability of the proposed TLD for high-rise building with about 60 stories. A real seismic wave was used, and the parameter of interest was chosen by the height of water level in the same shape of water tank. From the numerical results, the responses of structure with water tank were confirmed to be safer than those of structure without water tank.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2002.04a
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• pp.19-26
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• 2002

In this paper, the nonlinear structural analysis for the composite structure of the spent nuclear fuel disposal container and the 50cm thick bentonite buffer is carried out to predict the collapse of the container while the sudden rock movement of 10cm is applied on the composite structure. This sudden rock movement is anticipated by the earthquake etc. at a deep underground. Horizontal symmetric rock movement is assumed in this structural analysis. Elastoplastic material model is adopted. Drucker-Prager yield criterion is used for the material yield prediction of the bentonite buffer and von-Mises yield criterion is used for the material yield prediction of the container(cast iron insert, copper outer shell and lid and bottom). Analysis results show that even though very large deformations occur beyond the yield point in the bentonite buffer, the container structure still endures elastic small strains and stresses below the yield strength. Hence, the 50cm thick bentonite buffer can protect the container safely against the 10cm sudden rock movement by earthquake etc.. Analysis results also show that bending deformations occur in the container structure due to the shear deformation of the bentonite buffer. The elastoplastic nonlinear structural analysis for the composite structure of the container and the bentonite buffer is performed using the finite element analysis code, NISA.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2003.10a
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• pp.209-216
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• 2003

The purpose of this study is to investigate the response characteristics of pushover analysis of upper wall-lower frame system with X and Y-directions' lateral load Pushover analysis estimates initial elastic stiffness, post-yielding stiffness, and plastic hinges on each story of structures through three-dimensional nonlinear analysis program. The conclusions of this study are as follows; (1) As a result of pushover analysis, the magnitude of nonlinear response and distribution of yield hinge in lower structure are similar with both X and Y directions, but not in upper structure because of different relative stiffness. (2) The maximum drift ratio of roof is larger for X-direction than for Y-direction with respect to magnitude of shear wall areas in upper structure.

• Proceedings of the Korea Electromagnetic Engineering Society Conference
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• 2005.11a
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• pp.197-202
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• 2005

In this paper, we analyzed the signal distortion incorporating meander-shaped transmission line on PCB in broadband frequency range, up to 50GHz. This broadband characteristic provides reasonable analysis of digital pulse having very short rising time. Simulation results reveal suppression characteristic at multiband which is dependent on only the width of meander arm. This width of arm also can be adjusted using different permittivity because it provides different effective wave-length. It is found that the suppression characteristic shows sharpness with as a function of the number of arms. However, these characteristics shown limitation for microstrip line structure rather than for stripline structure, so we can avoid these unwanted phenomena using stripline structure.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.405-412
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• 2006

Among the various problems involved in the structural analysis of the Korean traditional wooden structure, the analytical model for the Kong-Po is controversial subject as usual. While some experiments are tried for establishing the basis of analytical models, most of these experiments are performed using scale down specimens. So, it is not possible to apply these experimental results to structural analysis of Korean traditional wooden structure directly. A numerical study for analogizing the stiffness of full scale Kong-Po structure is performed on the basis of experimental specimen. Some parameter studies using finite element method are made in this study. The finite element analysis used in this study is geometric material nonlinear analysis. The stiffness of Kong-Po structure found out in this study can be used for modelling the joints of the Korean traditional wood structure in frame analysis.

• Structural Engineering and Mechanics
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• v.42 no.4
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• pp.571-587
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• 2012

This paper presents results of a numerical analysis performed on a corrugated steel plate (CSP) bridge during a backfilling process. The analysed bridge structure was a box culvert having a span of 12315 mm as well as a clear height of 3550 mm. Obtained calculation results were compared with the experimental ones. The paper is presented with the application of the Fast Lagrangian Analysis of Continua (FLAC) program based on the finite differences method (FDM) to determine behaviour of the soil-steel bridge structure during backfilling. The assumptions of a computational 2D model of soil-steel structure with a non-linear interface layer are described. Parametric analysis of the interface element is also given in order to receive the most realistic calculation results. The method based on this computational model may be used with large success to design calculations of this specific type of structure instead of the conventional and fairly inaccurate analytical methods. The conclusions drawn from such analysis can be helpful mostly for the assessment of the behaviour of steel-soil bridge structures under loads of backfilling. In consideration of an even more frequent application of this type of structure, conclusions from the conducted analysis can be generalized to a whole class of similar structural bridge solutions.