• Composites Research
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• v.36 no.6
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• pp.388-394
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• 2023

In composites manufacturing, increasing resin impregnation is a key way to speed up the manufacturing process and improve product quality. While resin improvement is important, simple fiber surface treatments can also improve resin flowability. In this study, different plasma treatment times were applied to carbon fiber fabrics to improve the impregnation between resin and fiber. Electrical resistivity measurements were used to evaluate the dispersion of resin in the fibers, which changed with plasma treatment. The effect of fiber surface treatment on resin spreadability could be observed in real time. When inserting a carbon fiber tow into the resin, the amount of resin that soaked into the tow was measured to objectively compare resin impregnation. Five minutes of plasma treatment improved the tensile and compressive strength of the composite by more than 50%, while reducing the void content and increasing the fire point impregnation flow rate. Finally, a dynamic flexural fatigue test was conducted using a portion of the composite used as an architectural composite part, and the composite part did not fail after one million cycles of a 3 kN load.

• Journal of the Korea Institute of Building Construction
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• v.9 no.5
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• pp.155-161
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• 2009

This paper is the result of an investigation of a PORTABLE SLIP METER(ONO PPSM) by means of an experiment to determine its validity as a slip meter. ONO PPSM is a portable slip meter that was designed to address the weak points of PULL SLIP METER(O-Y PSM), which can be used to obtain an accurate measurement of slip resistance, but is very heavy and difficult to operate. To determine the stability of the measurement result of ONO PPSM, we measured the slip resistance against 4 different kind of floor materials. Our findings showed that the coefficient of variability of CSR' is less than 0.05. Furthermore, we verified the relationship between CSR' and CSR. More specifically, by performing the slip test against 7 different kinds of inorganic matter floor materials, we increased the usability of ONO PPSM as a slip meter by suggesting a method of sharing the evaluation index of slip of CSR' and C.S.R.

• Journal of the Korea Institute of Building Construction
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• v.15 no.1
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• pp.133-141
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• 2015

The floor slipperiness is an essential property for the pedestrian safety. This study was conducted to develop the slip test apparatus to be well accorded with actual characteristics of human gait; and the correlation between RCOF (Required coefficient of friction), Rz (Surface roughness), and 3 coefficients of slip resistance (C.S.R (Coefficient of slip resistance), BPN (British pendulum number), and SCOF (Static coefficient of friction)) were analyzed. Result of the analysis revealed that the cadence, stride length, and step length were proportional to the walking speed, and the significant correlation between walking speed and RCOF was found. However, the correlation between RCOF and the other respective coefficients of slip resistance was almost unidentified thus it would be difficult to identify the actual property of floor slipperiness with the RCOF alone.

• Journal of the Korea Institute of Building Construction
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• v.10 no.4
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• pp.3-9
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• 2010

Fire resistance and material properties of high-strength concrete (W/B 21.5%, 28.5%) with OPC, BS and FA were tested in this study. Main factors of the test consisted of fiber mixing ratio and W/B. Two types of fiber (NY, PP) mixed with the same weight were used for the test. The fiber mixing ratios were 0%, 0.05%, 0.1%, and 0.2% of the concrete weight. After performing the test, Under the W/B level of 21.5% and 28.5%, the spalling was effectively resisted by using the high strength concrete with fiber mixing ratios of 0.05%~0.1%. Compressive strength, flowability and air content are similar those of the fiberless high-strength concrete with the same W/B.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.705-708
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• 2008

Diatomite, bentonite and zeolite were used as porous materials for fabricating hygroscopic panels. Moisture adsorption and desorption of porous materials were investigated and hydrothermal method was applied to fabricate panels. Cheolwon diatomite and Pohang zeolite showed excellent characteristics of moisture adsorption and desorption. These characteristics were caused by higher surface area and pore volume of porous materials. Moisture adsorption contents were influenced by surface area and pore volume of panels, and surface area more effected on moisture adsorption. Moisture adsorption content of panel with 10% Pohang zeolite was 180g/m$^2$and that of 10% Cheolwon diatomite was 170g/m$^2$. Moisture desorption content of panel with 10% Pohang zeolite was 105g/m$^2$. Moisture adsorption contents of panel with porous materials were higher than that of panel without porous materials.

• Journal of the Korea Institute of Building Construction
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• v.16 no.1
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• pp.17-24
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• 2016

Recently, exposed concrete by machinery trowel is generally used in industrial floor such as warehouse. Also, concrete using only the cement has been mainly used except mineral admixture in order to secure surface abrasion resistance. However, in hot weather construction, it is causing a serious problem such as workability inhibition of trowel using only ordinary portland cement. Due to this, it was investigated the effect of application of fly-ash and ground granulated blast furnace slag on properties and abrasion resistance of concrete for industrial floor in this study. The result of this study, it was confirmed that fly-ash and ground granulated blast furnace slag can be used in concrete for industrial floor without affecting significantly the properties of concrete.

• Journal of the Korea Institute of Building Construction
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• v.11 no.2
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• pp.181-188
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• 2011

Spalling must be considered when designing high-strength concrete to cope with fire. This study investigates the temperature rise of steel bar in high-strength concrete coated with fireproof mortar using gypsum exposed to fire. It was found that fireproof mortar using gypsum is more effective in constraining the temperature rise of steel bar in the high strength concrete than fireproof mortar using cement, and that the thinner the cover depth of the fireproof mortar, the more significant the influence of the gypsum. In addition, while there was no difference between ${\alpha}$-hemihydrate mortar and ${\beta}$-hemihydrate mortar on the temperature rise of steel bar, the compressive strength of ${\alpha}$-hemihydrate mortar is higher than that of ${\beta}$-hemihydrate mortar.

• Journal of the Korean Ceramic Society
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• v.40 no.8
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• pp.811-817
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• 2003

Recently, application fields of non-metallic minerals by utilizing their structure properties are broadening. Especially, layered minerals have not only excellent shielding or covering ability but also absorbing and storing characteristics of chemical elements between a layers. We considered about the above mentioned characteristics and added functional substances onto their surfaces for the preparation of new environmentally friendly functional materials. In this study, natural graphite and sericite were mainly used to produce for the new environmentally friendly functional building materials. Graphite surfaces were modified with a surfactant (Alkyl Benzyle Demethyle Ammonium Chloride) for anti-bacillus and penicillium. Surface modification mechanism are that primary adsorption by differential zeta potential between graphite and ABDM and secondary adsorption by interaction between surfactant chains take place. Surfactant layers were fully formed and it was expected up to 99.7% up the efficiency of anti-bacillus and penicillium. Also the prepared functional samples have a effect to improve a various efficiency such as electromagnetic wave shield(up to 95%), deodorization(up to 80%), heat storage(5%) etc.

• Proceedings of the KSR Conference
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• 2009.05a
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• pp.1109-1116
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• 2009

To the development of construction techniques and construction of glass-walled structure is generalized. Existing wall to support the role of the vertical load was lose. Features and the beautiful side of the curtain wall job was to be highlighted. Carriage access to the interior of the windows will cause pain in the neck with a cold feeling. And in the windows, drafty windows, under floor heating occurs despite the condensation phenomenon occurs. droplets that occurs around the window (the cause of the mold) in summer and winter, the heat energy and move through the glass is warmer outside. Therefore, to reduce energy efficiency affects absolutely. When you apply heat to the carriage window, the surface of the glass system, the spread of the cold air does not occur. Therefore, energy savings cars and heating of the interior is cold.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.9
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• pp.857-861
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• 2010

Recently photochemical smog has become a serious urban air pollution. And VOC is the major pollutant for it. With the advance of industrialization and urbanization, MSWI fly ash and sewage sludge and melting slag were generated. It is necessary to de-toxificate ashes, because they contain many toxic constituents and probably lead to contaminate the environment. The objective of this research was to prepare multi-functional brick which is able to remove VOCs in ambient air. The bricks were made of MSWI fly ash, sewage sludge and slag. The benzene adsorption experiment by brick was acted to evaluate its adsorptivity. And also photocatalyst material was coated to enhance its adsorptivity and the endurance on the brick. According to the result, the benzene showed 74~96%. The removal efficiency was increased and the breakpoint time was lengthened by coating a brick.