• Proceedings of the Korean Institute of Building Construction Conference
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• 2009.11a
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• pp.35-39
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• 2009

Recently, the flat-plate structure is widely used because it has many advantages such as reduction of story height, long span etc than the RC rahmen structure. Furthermore, application of the flat-plate is on the increase because of flexible plan unlike wall structure. Long span have been at a disadvantage for vibration serviceability evaluation, however studies about vertical direction vibration of flat-plate structure has not been carried out. This study analysis the characteristics according to slab structure to make an experiment on vibration and floor impact noise for the flat-plate structure in construction performance laboratory in Kolon E&C R&D center, the flat-plate structure applied to the post-tension method, and the wall structure in apartment houses.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.11a
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• pp.186-187
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• 2014

Flexural stress and fracture energy of fiber reinforced cementitious composites is increased by bridge effect of reinforced fiber, scabbing failure is restrained. Shape, properties of fiber were SF(steel fiber), PA(polyamide), NY(nylon) have effects on flexural stress and fracture energy, impact resistance improve of fiber reinforced cementitious composites. In this study, local failure properties by impact of high velocity projectile was analyzed by mixing 3 types of fiber which have different shape and properties respectively.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.3
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• pp.347-354
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• 2020

Site characterization for decommissioning Kori Unit 1 is ongoing in South Korea after 40 years of successful operation. Kori Unit 1's containment building is assumed to be mostly radioactively contaminated, and therefore radiation exposure management and detailed contamination investigation are required for decommissioning and dismantling it safely. In this study, site-specific Derived Concentration Guideline Levels (DCGLs) were derived using the residual radioactivity risk evaluation tool, RESRAD-BUILD code. A conceptual model of containment building for Kori Unit 1 was set up and limited occupational worker building inspection scenario was applied. Depending on the source location, the maximum contribution source and exposure pathway of each radionuclide were analyzed. The contribution of radionuclides to dose and exposure pathways, by source location, is expected to serve as basic data in the assessment criteria of survey areas and classification of impact areas during further decommissioning and decontamination of sites.

• Journal of Korean Society of Forest Science
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• v.90 no.2
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• pp.217-226
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• 2001

This study estimated the impacts of the building permit area change on the forest products import quantities in Korea. The first objective of this dissertation is to analyze whether there is any causal relationship between change in the building permit area and changes in the import quantities of forest products in Korea. Assuming that there is any causal relationship, the second objective is to evaluate the dynamics of the impacts of the building permit area change on the forest products import quantities in Korea. The relationship between the building permit area and the import quantity was represented by bivariate vector autoregressive or vector error correction model. Whether there is any causal relationship between change in the building permit area and changes in the import quantities of forest products was analyzed by the causality test of Granger. And the dynamics of the impacts of the building permit area change on the forest products import quantities were evaluated by variance decomposition analysis and impulse response analysis. The import quantity of forest products can be explained by the lagged building permit area variables and the lagged import quantity variables in Korea. Change in the building permit area causes change in the high-density fiberboard import quantity in Korea. In the bivariate model of the high-density fiberboard import quantity, after six months, the building permit area change accounts for about ten percent of variation in the import quantity, and its own change accounts for about ninety percent of variation in the import quantity. On the other hand, the impact of a shock to the building permit area is significant for about six months on the import quantity of high-density fiberboard in Korea. That is, if the building permit area change indeed had an impact on the import quantity of high-density fiberboard in Korea, it was only of a short-term nature.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.193-194
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• 2017

Effect of variable factors on carbon emissions in construction industry is hard to analysis. Therefore this study analyzies effect of variable factors on carbon emissions. This study shows importance of variable factors and emphasizes need of estimation of carbon emissions considering variable factors.

• International journal of advanced smart convergence
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• v.13 no.3
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• pp.367-375
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• 2024

Draft curtains are an important tool to reduce the spread of fire smoke in buildings. This paper mainly studies the influence of draft curtains on smoke spread in a hospital outpatient building with a spacious hall. The outpatient building of a county hospital in China is taken as the research object, and a fire simulation model is established based on PyroSim software. Four scenarios are designed: no draft curtains in the hall, draft curtains with a length of 1.5m in the hall, draft curtains with a length of 2.0m in the hall, and draft curtains with a length of 2.5m in the hall. At the same time, considering the worst situation, only the main emergency exit is opened, while the remaining emergency exits and windows are all closed, and the fire-fighting facilities are not activated. The detection point is set at the open emergency exit, 1.8m above the ground. Through the simulation of four scenarios, the effect of draft curtains on smoke spread is discussed from four aspects: smoke layer height, temperature, visibility, and CO concentration. The results show that draft curtains have a significant impact on the spread of smoke in a hospital outpatient building with a spacious hall. The longer the draft curtains are, the better the smoke-blocking effect. It should be noted that in the actual design, the length of the draft curtains should be considered without affecting the evacuation of personnel.

• Computers and Concrete
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• v.17 no.4
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• pp.455-475
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• 2016

Dynamic characteristics, named as natural frequencies, damping ratios and mode shapes, affect the dynamic behavior of buildings and they vary depending on the construction stages. It is aimed to present the effects of construction stages on the dynamic characteristics of reinforced concrete (RC) buildings considering theoretical and experimental investigations. For this purpose, a three-storey RC building model with a 1/2 scale was constructed in the laboratory of Civil Engineering Department at Karadeniz Technical University. The modal testing measurements were performed by using Operational Modal Analysis (OMA) method for the bare frame, brick walled and coated cases of the building model. Randomly generated loads by impact hammer were used to vibrate the building model; the responses were measured by uni-axial seismic accelerometers as acceleration. The building's modal parameters at these construction stages were extracted from the processed signals using the Enhanced Frequency Domain Decomposition (EFDD) technique. Also, the finite element models of each case were developed and modal analyses were performed. It was observed from the experimental and theoretical investigations that the natural frequencies of the building model varied depending on the construction stages considerably.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.149-150
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• 2021

Earthwork is the starting work of construction process, which has the greatest impact on the productivity of the construction project among the works. However, it is difficult to derive accurate productivity becuase the earthwork plan is affected by geological condition of the jobsite. Therefore, a simulation model for productivity analysis of earthwork was developed using CYCLONE modeling method in this study. In this paper, simulation model was made considering the impact factors of earthwork productivity. The proposed model can be utilized for sensitivity analysis in future studies.

• International Journal of Precision Engineering and Manufacturing
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• v.2 no.2
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• pp.5-10
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• 2001

This paper attempt to explore the shape of stress wave propagation of 3-dimensional stress field which in made in the process of the time increment. A finite element program about 3-dimensional stress wave propagation is developed for investigating the changing shape of the stress by the impact load. The finite element program, which is the solution for the 3-dimensional stress wave analysis, based on Galerkin and Newmark-${\beta}$ method at time increment step. The tensile stress and compressive stress become larger with the order of the middle , the upper and the opposite layers when the impact load is applied. In a while the shear stress become larger according to the order of the upper, the middle and the opposite layers when impact load applied.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05a
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• pp.191-194
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• 2005

Recently the heavy weight impact noise transmitted slab vibration has been recognized as an important issue. The aim of this study is to find the path of vibration transmission, comparing the numerical analysis with the field test results. Additionally the effect of stiffening beam element under slab, as a method to increase the stiffness of slab, will be shown concerning natural frequencies.