• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.5
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• pp.413-420
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• 2014

The purpose of this study is to experimentally investigate the shear behavior of flat plate that reinforced by embedded GFRP(glass fiber reinforced polymer) plate with openings. Shape of the GFRP shear reinforcement is a plate with several openings to ensure perfect integration with concrete. The test was performed on 7 specimens to check shear strength of flat plate that reinforced by GFRP plate. The parameters include the spacing of the shear reinforcement and amount of the shear reinforcement. The result of test showed that when amount of shear reinforcement was increased, shear strength improved. The result of test showed that maximum shear strength was confirmed when spacing of shear reinforcement was 0.3d. The calculation of the shear strength of reinforced flat plate with GFRP plate based on the KCI was compared with the test results.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.4 no.2
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• pp.443-451
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• 2000

Until now, there have been various kinds of science information databsae which databased the science technology information, but they do not satisfy the aspiration of the users. Therefore, in the position of the users, it suggests the technology information space as a now paradigm, which supplement the function of science information DB. ICPIS which inputs described papers with keywords, offers the itemized summary of these contents, the visual indication and comparison of similar thesis, and it also supplises the abundant summary information, survey information, more than ten volumes of info communication thesis with starting the casual relation extraction for the users, playing a significant role in ICPIS is called KP, and it is package of domain knowledge that unifies the extraction and structure narration of the technology information. ICPIS extracts the technology information among the thesis that are deserved by the natural language treatment in the itemized KP keywords described, and form the prescribed summary structure in KP.

• Journal of the Korean Society for Advanced Composite Structures
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• v.2 no.2
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• pp.7-12
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• 2011

Presently, composite method for steel and concrete is often used the stud. Steel properties of composite column could be changed by increasing of welding. The changed properties is possibly to cause local-buckling. Composite column had a large effect by slip instead of pull-out force in comparison composite girder. Improvement of adhesive force had effect by contact area rather than height of stud in composite column. This paper proposed new type of stud and analyzed performance through experimental study. This method would be effect steel structure with curvature.

• Journal of the Korea institute for structural maintenance and inspection
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• v.24 no.4
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• pp.81-90
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• 2020

A textile and capillary tube composite panel(TCP) was developed to simultaneously retrofit the seismic performance and the energy efficiency (e.g. heating or insulation performance) of existing unreinforced masonry (URM) buildings. TCP is a light-weight mortar panel in which carbon textile reinforcements and capillary tubes are embedded. Textile reinforcements plays a role of seismic retrofit and capillary tubes that hot water circulates contribute to the energy retrofit. In this paper, the static cyclic loading tests were performed on the masonry walls with/without TCP to understand the seismic retrofit effect of TCP retrofit and the results were summarized. The results of the test showed that the TCP contributed to increase the capacity of the Shear strength and ductility of the URM walls. In addition, the deformation of the wall after cracking was substantially controlled by the carbon textile.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.2
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• pp.121-128
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• 2014

In this study, The purpose of this study is to experimentally investigate the shear behavior of reinforced flat plate embedded with GFRP(glass fiber reinforced polymer) plate with openings. The GFRP shear reinforcement is manufactured into a plate shape with several openings to ensure perfect integration with concrete. The test was performed on 7 specimens. the parameters include the type of reinforcement and amount of the shear reinforcement., From the test, we analysed the crack, failure mode, Strain, load-displacement graph. a calculation of the shear strength of reinforced flat plate with GFRP plate based on the ACI 318-11 was compared with the test results. The results of the experiment indicate that GFRP plate is successfully applied as a shear reinforcement in the flat plate under punching shear.

• Journal of the Computational Structural Engineering Institute of Korea
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• v.27 no.4
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• pp.247-254
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• 2014

In this study, shear test performed to investigate the shear behavior of flat plate that reinforced by embedded GFRP(glass fiber reinforced polymer) plate with openings. Shape of the GFRP shear reinforcement is a plate with several openings to ensure perfect integration with concrete. The test parameters include the distance between the column face and the first line of GFRP plate and number of GFRP plate vertical strip. The result of test showed that when number of GFRP plate vertical strip was increased, shear strength improved. The shear strength for flat plate reinforced GFRP plate in various codes including ACI 318, BS 8110, EUROCODE 2, and KCI were compared to provide more rational approach for reinforced concrete flat plates with GFRP plate.

• Composites Research
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• v.31 no.6
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• pp.323-331
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• 2018

The effect of stainless steel jagged-pin reinforcement on the pull-off strength of the composite hat-joint was studied by the test. The pins were physically and chemically surface-treated and inserted in the thickness direction over the interface where the skin and stiffener meet. The specimens including the jagged-pins were made by co-curing process. Diameters of the jagged-pins were 0.3, 0.5 and 0.7 mm. The pin areal densities were set to 0.5 and 2.0% based on the interface area where the skin and stiffener meet. The specimens using 0.3 mm diameter normal (un-jagged) pins with 2.0% areal density were additionally fabricated and tested to investigate the pin shape effect on the pull-off strength. The pull-off strengths of specimens reinforced with 0.5% areal density by 0.3, 0.5, and 0.7 mm diameter pins were 45, 19 and 9% higher than those of un-reinforced specimens, respectively. In case with 2.0% pin areal density, the strengths were 127, 45, and 11% higher than those of un-reinforced specimens, respectively. The test results show that the higher pin areal density results in the higher strength when the pin diameter is the same. When the pin areal density is the same, the smaller pin diameter leads to higher strength. When the joints using jagged-pins and normal pins in 2.0% areal density with 0.3 mm diameter, the joints of jagged-pins showed the 64% higher strength. From the results of this study, it was confirmed that jagged-pin reinforcement can be an effective method for improving the pull-off strength of composite hat-joint.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.12
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• pp.8700-8706
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• 2015

The first driving device of the power bogies for the Korean high-speed railway vehicle consists of the traction motor (TM) and the motor reduction gears unit (MRU). Although TM and MRU are the mechanically integrated structures, their time between overhauls (TBO) have two separate intervals due to different technical requirements(i.e. TBO of MRU: $1.8{\times}10^6km$, TBO of TM: $2.5{\times}10^6km$). Therefore, to reduce the unnecessary number of preventive maintenances, it is important to evaluate the optimal TBO with a viewpoint of reliability-center maintenance towards cost-effective solution. In this study, derived from the field data in maintenance, fault tree analysis and failure rate of the subsystem considering criticality of the components are evaluated respectively. To minimize the conventional total maintenance cost, the same optimal TBO of the components is derived from genetic algorithm considering target reliability and improvement factor. In this algorithm, a chromosome which comprised of each individual is the minimum preventive maintenance interval. The fitness function of the individual in generation is acquired through the formulation using an inverse number of the total maintenance cost. Whereas the lowest common multiple method produces only a four percent reduction compared to what the existing method did, the optimal TBO of them using genetic algorithm is $2.25{\times}10^6$km, which is reduced to about 14% comparing the conventional method.

• Journal of the Society of Disaster Information
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• v.14 no.2
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• pp.107-114
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• 2018

Purpose : This study is to develop walls using wall recording technology applied on roofs to prevent fire spread in traditional markets. Method : The spray head installed on the developed wall was designed so that the fire does not spread to adjacent buildings after being used for plants. In addition, a spray head was attached to the upper section and some sections for the growth of plants planted on the wall to prevent the spread of fire. Results : These technologies suggested the development of walls that can be installed at the upper level of buildings, such as traditional markets, and separate isolation facilities were not necessary because they are integrated with structures and sprinklers. In addition, sprinklers can perform both the plant spray and fire spread prevention functions. It is believed that this is the only alternative technology proposed in Korea to prevent the spread of fire. Conclusion : In this study, the wall design, designed directly to derive the quantitative performance of the fire spread reduction effect, demonstrated the fire suppression method of the wall system, the durability of the wall itself, and the flame retardability performance.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.22 no.2
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• pp.67-72
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• 2010

In this study, the impact on the circulating water system has been analyzed due to an installation of helical turbine to develop hydro-kinetic energy at the discharge channel of the power plant. Numerical simulations of velocity and pressure variations have been performed when one set of $3.6\;m\;{\times}\;1.5\;m$ sized helical turbine is installed at the outlet of discharge culvert. In case of mean sea level, change of downstream water surface elevation does not affect upstream elevation of the weir because its propagation is blocked by the seal well weir. However in case of highest high water level, change of downstream elevation affects upstream elevation because flow pattern in discharge culvert becomes the full pipe flow with submerged weir. Although an unstable pressure change occurs in upstream of the weir during the intial 10 minutes after beginning of the discharge, it becomes stable after that time. In addition, a rise of water surface elevation by 0.2 m is observed but it is concluded that it hardly affects the safety of circulating water pump (CWP) although its required power is increased more or less. Therefore, the increase of required power of CWP needs to be considered for evaluation of the helical turbine applicability.