• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.577-578
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• 2009

For cases where the column concrete strength exceeds 1.4 times the slab concrete strength, the KCI Code requires that either: puddled high-strength concrete(HSC) be used in the slab, or the use of vertical dowels and spirals through the joint, or the use of an effective concrete strength in the joint. This paper studies on the third strategy. A prediction model of the effective concrete strength for interior columns was proposed using an analogy of brick and mortar in brick masonry. The proposed prediction model is verified by comparison with experimental results and various design equations.

• Journal of Korean Association for Spatial Structures
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• v.6 no.2 s.20
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• pp.85-92
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• 2006

Precast large panel structures have various connection system such as the horizontal slab-to-wall connection, the vertical wall to wall connection, horizontal slab-to-slab connection, etc. Horizontal connection is connected by vertical tie bars, and vertical joint is connected loop bars and shear keys. The basic function is equalized deformations on later forces and the entire wall panel assembly acts as monolithic actions. Under lateral load some slip occurs in almost vertical connections. The shape and detail of precast connections are very important to the monolithic behavior of overall structures. The paper is a study on the design method and new elasto-plastic analysis of the connections by rigid-bodies spring model.

• Proceedings of the Computational Structural Engineering Institute Conference
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• 2006.04a
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• pp.333-340
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• 2006

In these days the floor vibration is beginning to make its appearance of the environmental dispute in apartment building. Standard floor system are suggested for the settlement of this issue by government. The sound of floor impact sound is needed to secure comfortable quality in housing. Also, it is required an accurate analysis and a proper evaluation for floor vibration. Refine model is necessary for the floor system of housing to analyze accurately the floor vibration. But this refine model is not efficient because it is required so much running time for vibration analysis and it is difficult of modeling of standard floor slab. In this paper, new modeling methods of standard floor slab are proposed for the accurate rigidity evaluation. By using the new modeling method, the accurate vibration response can be obtained and can accurately evaluate the rigidity of standard floor system with resilient materials. Therefore the proposed modeling method is of practical use for vibration analysis of floor system of apartment building.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.327-329
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• 2012

The validity of the numerical model used in the program is established by comparing the prediction from the computer program with results from full-scale fire resistance tests. Details of fire resistance experiments carried out on reinforced concrete slab, together with results, are presented. The results obtained from experimental test indicated in that the proposed numerical model and the implemented codes are accurate and reliable.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 1997.10a
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• pp.143-150
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• 1997

Generally, the problem of vertical vibration of structure is generated slab. Analysis of space framed structures with slab for vertical vibration requires more efficient modeling and analysis technique, because number of elements lead to more complicated model with many degree of freedom which requires large amount of computing resources for dynamic analysis. This paper propose an efficient analysis method for vertical vibration of space framed structure with slab. At first, proposed model is selected minimum joints and degree of freedom which are acquired sufficient dynamic response to the vertical vibration. Secondly, super-elements that are made a number of element are used for simple input data and fast analysis.

• Journal of the Korean Society of Combustion
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• v.11 no.1
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• pp.34-42
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• 2006

Numerical analysis code has been developed to investigate the slab heating characteristics in a reheating furnace of a steel mill company. Unsteady 3-Dimensional behaviour can be predicted with the developed code. Premixed flame model is adopted for combustion phenomena and eddy dissipation model is used for turbulent combustion. Non -gray FVM radiation method is used to get a better accurate radiative solution. Slab movement can be fully traced from entrance into a reheating furnace until it#s exit and computation is performed during that period.

• Steel and Composite Structures
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• v.23 no.1
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• pp.115-130
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• 2017

A new type of moment-resisting bolted connection was developed for use in composite steel- concrete construction to connect composite open section steel beams to concrete filled steel square tubular columns. The connection was made possible using anchored blind bolts along with two through bolts. It was designed to act compositely with the in-situ reinforced concrete slab to achieve an enhanced stiffness and strength. The developed connection was incorporated in the design of a medium rise (five storey) commercial building which was located in low to medium seismicity regions. The lateral load resisting system for the design building consisted of moment resisting frames in two directions. A major full scale test on a sub-assembly of a perimeter moment-resisting frame of the model building was conducted to study the system behaviour incorporating the proposed connection. The behaviour of the proposed connection and its interaction with the floor slab under cyclic loading representing the earthquake events with return periods of 500 years and 2500 years was investigated. The proposed connection was categorized as semi rigid for unbraced frames based on the classification method presented in Eurocode 3. Furthermore, the proposed connection, composite with the floor slab, successfully provided adequate lateral load resistance for the model building.

• Proceedings of the KSR Conference
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• 2008.06a
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• pp.691-706
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• 2008

ATP(Automatic Train Protection) system in railway signaling system is the important one grasping the position and velocity of a train. The wayside transmitter of ATP system is installed between rails. In concrete slab track, the signal current using wayside transmitter of ATP system is influenced by reinforcing bars. The magnetic coupling between reinforcing bars and wayside transmitter of ATP system as a filter makes an input current distorted. So, it makes an alternating current signal with a desirable size not transmit to on-board system of a train. Way to decrease the distortion of an input current signal frequency is to avoid maximum induction current frequency. And the induction phenomenon between reinforcing bars insulated and wayside transmitter of ATP system does not occur. In this paper, we represent the model about wayside transmitter of ATP system and reinforcing bars on the concrete slab tracks, and calculated the parameters demanded for the model. Also, we demonstrated it through the Maxwell program. Furthermore, we calculated impedance on wayside transmitter used in KVB system and ERTMS/ETCS system which are a kind of ATP system, frequency response of induction current, using the Matlab, and demonstrated the validity of it, using the PSpice program.

• Journal of the Earthquake Engineering Society of Korea
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• v.21 no.5
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• pp.255-264
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• 2017

Dynamic numerical simulation of pile-supported slab track system embedded in a soft soil and embankment was performed. 3D model was formulated in a time domain to consider the non-linearity of soil by utilizing FLAC 3D, which is a finite difference method program. Soil non-linearity was simulated by adopting the hysteric damping model and liner elements, which could consider soil-pile interface. The long period seismic loads, Hachinohe type strong motions, were applied for estimating seismic respose of the system, Parametric study was carried out by changing subsoil layer profile, embankment height and seismic loading conditions. The most of horizontal permanent displacement was initiated by slope failure. Increase of the embedded height and thickness of the soft soil layer leads increase of member forces of PHC piles; bending moment, and axial force. Finally, basic guidelines for designing pile-supported slab track system under seismic loading are recommended based on the analysis results.

• Proceedings of the Earthquake Engineering Society of Korea Conference
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• 2003.09a
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• pp.191-198
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• 2003

Flat slab system has been adopted in many buildings constructed recently because of the advantage of reduced floor heights to meet the economical and architectural demands. Structural engineers commonly use the equivalent frame method(EFM) with equivalent beams proposed by Jacob S. Grossman in practical engineering for the analysis of flat slab structures. However, in many cases, when it is difficult to use the EFM, it is necessary to use a refined finite element model for an accurate analysis. But it would take significant amount of computational time and memory if the entire building structure were subdivided into a finer mesh. An efficient analytical method is proposed in this study to obtain accurate results in significantly reduced computational time. The proposed method employs super elements developed using the matrix condensation technique and fictitious beams are used in the development of super elements to enforce the compatibility at the interfaces of super elements. The stiffness degradation of flat slab system considered in the EFM was taken into account by reducing the elastic modulus of floor slabs in this study. Static and dynamic analyses of example structures were peformed and the efficiency and accuracy of the proposed method were verified by comparing the results with those of the refined finite element model and the EFM.