• Journal of the Korean Society of Marine Environment & Safety
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• v.26 no.5
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• pp.454-465
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• 2020

Fire simulations were performed using the Fire Dynamics Simulator (FDS) software to examine the vent flow and temperature in the engine room of a small ship. A diesel fire with a heat release rate of 10 kW was targeted, and the effects of the ceiling duct location, side vent existence and nonexistence, and side vent size were investigated. The existence or nonexistence of the side vent and its size considerably affected the smoke behavior, mass flow rate through the vent, and temperature. When the side vent was not installed or was small, the smoke layer reached the floor in the engine room. In addition, as the side vent size increased, the mass flow rate through the vent increased with decreasing temperature value. However, the effects of the ceiling duct location on the smoke behavior, mass flow rate through the vent, and temperature seemed to be relatively minor compared to those of the side vent size. Therefore, to improve the fire safety of the engine room in a small ship, the side vent size is considered to be a more important design factor than the ceiling duct location.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.6
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• pp.138-145
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• 2020

This study was conducted to identify the structural performance of the opening in a location close to the support point in the perforated beam system of steel beams. In addition, structural performance was determined through experiments on reinforced openings using vertical and horizontal steel plates. In the steel simple beam, it was found that the opening was in a position closer to the support point, half the height of the steel beam (D/2), which was more appropriate than the height of the steel beam (D). In addition, the reinforcement effect of horizontal steel plate was greater than that of vertical steel plate reinforcement. Structural performance was improved when there was no gap between openings and steel plates.

• Journal of the Korea Concrete Institute
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• v.15 no.5
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• pp.697-704
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• 2003

The purpose of this experimental study is to investigate the relationship of the shear behavior and the variety of width, depth and location of an opening in reinforced concrete deep beams with rectangular web openings, and to present an improved shear strength equation of those members. The main parameters considered were concrete strength(fck), shear span-to-overall depth ratio(a/h), and the size and vortical position of the web openings. Twenty five deep beams were tested under two symmetric loading-points. Test results showed that the shear behavior of deep beams with web openings was influenced by a/h and the size of opening. In addition, the KCI shear design provision is a tendency to be more unconservative according to the increase in a/h and the area-ratio of opening to shear span(Ao/Ash). Based on the concrete strut action of top and bottom member of an opening and the tie action of longitudinal reinforcement, a proper design equation which closely predicts the capacity of deep beams with rectangular openings is developed.

• Journal of Korean Society of Steel Construction
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• v.21 no.3
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• pp.233-243
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• 2009

The objective of this study was to investigate the effect of openings on the structural behavior of SC walls. The FEM program ABAQUS was used in this analytical study. The main parameters were the locations and sizes of the openings: a total of 20 locations and a total of four opening sizes were adopted. The analysis results were compared with the results of the currently applied evaluation methods. The strength reduction factor method may be used to safely design SC walls with openings. The strength reduction factor of the effective strut method is more similar to that of the analysis results.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2000.11a
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• pp.176-182
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• 2000

철도교에서 철도역사의 경우 도로교와 달리 승객의 이동시 필요한 승강장이 존재하기 때문에 승강장의 통로를 위해 개구부가 존재할 수밖에 없다. 따라서 철도교의 철도역사에 대한 구조해석 시 슬래브에 위치한 개구부에 대한 고려가 필수적이다. 그러나 최근까지의 철도교의 철도역사에 대한 구조해석은 2차원 평면 해석에 의존하는 경우가 많아서 개구부에 대한 고려가 없거나 소홀했던 것이 사실이다.(중략)

• Journal of the Computational Structural Engineering Institute of Korea
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• v.15 no.2
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• pp.237-249
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• 2002

The wall system that is composed only of reinforced concrete walls and slabs is adopted on many high-rise apartment buildings recently constructed. In the apartment buildings, a shear wall may have one or mote openings for functional reasons. Many researches on the analysis of shear wall with openings were performed. But, some restrictions prevent those research results being applied to practical analysis and design procedure. It is necessary to use subdivided finite elements lot accurate analysis of the wall system with openings. But it would cost tremendous amount of analysis time and computer memory if the entire building structure is subdivided into a finer mesh. An efficient analysis method which can be used regardless of the number, size and location of openings is proposed in this study. The analysis method uses super element, matrix condensation technique and fictitious beam technique. Analyses of example structures having various types of openings were performed to verify the efficiency of proposed method. It was confirmed that the proposed method have outstanding accuracy with drastically reduced time and computer memory from the analyses of example structures.

• Journal of Korean Association for Spatial Structures
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• v.8 no.3
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• pp.53-63
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• 2008

In this study, the reverberation characteristics of coupled spaces were investigated using a scale model. Two rooms were connected through an acoustically transparent opening known as an aperture. The acoustic characteristics of the coupled room by varying three parameters, the aperture opening size, the absorption ratio between the two rooms and the locations of the secondary room, were measured and analysed. The results indicated that a reverberant secondary room, produced large variations of the acoustics in the main room and an absorptive secondary room was effective to provide systematic control of the acoustics in the main room. The reverberant secondary room should be located at the rear of the stage and the aperture opening ratio over 6.25% produced large variations of the acoustics in the main room. However, the aperture opening ratio over 25% had no effect on variations of the acoustics in the main room. The absorptive secondary room should be located at the rear of the audience areas and the aperture opening ratio over 3.13% produced large variations of the acoustics in the main room.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.5A
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• pp.277-287
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• 2012

The shear wall with openings built with reinforced concrete (RC) have been elaborately studied by many researchers, whereas the steel plate concrete (SC) wall structure has not been investigated as much. The recent SC wall structures developed in Korea have been partly applied to nuclear power plant structures, although its design specification or guideline for the SC wall structure with openings has not been completed yet. This study based on numerical analysis evaluates the effects of opening on the structural resistance of the SC structure in nuclear power plant. As a result from nonlinear analysis, since the strengthening for openings significantly affect the overall strength of SC wall, the openings should be considered to strengthen them around adjacent area. It is also proved that the strengthened openings have the sufficient resistance and ductility regardless their size, shape, location, and quantity.

• Journal of the Korea institute for structural maintenance and inspection
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• v.25 no.2
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• pp.66-73
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• 2021

In the existing study of steel beams with openings, openings are located at a location where the distance to the support point is equal to or greater than the section height. Considering the facilities using the openings in the steel beam, the distance from the opening to the support point may be closer than the height of the beam section. Therefore, research on this is needed. This study is an experimental study to understand the structural performance of beams with openings close to the ends subjected to Cyclic Loading. In addition, in this study, we want to understand the structural performance through experiments on beams with openings reinforced with vertical or horizontal steel plates.

• Journal of Korean Society of Steel Construction
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• v.13 no.5
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• pp.513-524
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• 2001

A total of nine H-shaped beams with web openings under cyclic loading condition were investigated. The dimension criteria are based on the formulae proposed by Darwin. The suitability of existing design formulae the effects of plastic hinge on beams with web openings the fracture around the web openings and the influence of cracks neighboring web openings to the beam strength under cyclic loading were also investigated through the observation of the behavior of these beams with various opening dimensions. locations numbers and spacing between the two openings.