• Journal of the Korea Concrete Institute
• /
• v.26 no.4
• /
• pp.421-428
• /
• 2014

This paper describes the experimental results of insulated concrete sandwich wall panels (CSWP) with corrugated glass fiber-reinforced polymer (GFRP) shear connectors under in-plane shear loading. Corrugated GFRP shear connectors were used to improve the thermal property of insulated CSWP and to achieve composite action between the interior and exterior concrete wall panels. Test specimens were consist of three concrete panels with two insulation layers between concrete panels and middle concrete panels was loaded in the direction of gravity. To evaluate the effects of insulation types (extruded polystyrene, XPSS and expanded polystyrene, EPS), shear connector pitch (300 and 400 mm) and width (10 and 15 mm) on in-plane shear behavior of insulted CSWP, failure mode and shear flow-average relative slip relationship of specimens were investigated. Test results indicate that the bond stress between concrete panel and insulation is considerable initially. Especially in case of insulated CSWP without shear connector, initial stiffness of CSWP with XPSS is superior to that of CSWP with EPS. The shear connector's contribution to in-plane shear performance of insulated CSWP depends on the type of insulation.

• Journal of Advanced Marine Engineering and Technology
• /
• v.36 no.8
• /
• pp.1097-1103
• /
• 2012

There are many fish farms being cultivated in the southwestern cost of South Korea. Because the farms cultivating use the basic method that inflow and circulate sea-water, slight negligence and bad design cause major negative impact on fish deaths. Also, the optimal temperature for each specie of fishes has already been proven to differ on each specie. Maintaining this environment, regardless of seasons, is very difficult and that requires research to develop. In this paper, basic characteristics of heat and mechanism of heat transfer are studied. Based on this, Open-end water vessel is designed and constructed using sandwich-insulation panels and simulated to store the heat in certain isolated space. This study confirmed that it is possible to keep constant temperature by this method, in large areas of water where it is insulated by heat insulator. and equipped with heater in Open-end water vessel where the other part is heated. The AC power controller maintains the constant temperature required and the temperature controller detects and displays the temperature by using the micro-processor.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2018.05a
• /
• pp.21-22
• /
• 2018

Foamed concrete is a porous concrete that is cured by mixing bubbles into cement slurry. It is lighter than ordinary concrete and is characterized by higher insulation. Lightweight foamed concerte is mainly used as a sandwich panel in Korea, and is also used as a refractory filler in fireproof safes. Studies on lightwight foamed concrete have been carried out on strength,density and thermal conductivity. However, it is confirmed that the research on the fire resistance performance is very limited. Based on this study, fire resistance of lightweight foamed concrete using expanded polystyrene beads is investigated.

• Journal of the Korea Institute of Building Construction
• /
• v.9 no.4
• /
• pp.63-73
• /
• 2009

Recently, the use of lightweight panels in building structures has been increasing. Of the various lightweight panel types, styrofoam sandwich panels are inexpensive and are excellent in terms of their insulation capacity and their constructability. However, sandwich panels that include organic material are quite vulnerable to fire, and thus can numerous casualties in the event of a fire due to the lack of time to vacate and their emission of poisonous gas. On the other hand, lightweight foamed concrete is excellent, both in terms of its insulation ability and its fire resistance, due to its Inner pores. The properties of lightweight concrete is influenced by foaming agent type. Accordingly, this study investigates the insulation properties by foaming agent type, to evaluate the possibility of using light-weight foamed concrete instead of styrene foam. Our research found thatnon-heating zone temperature of lightweight foamed concrete using AP (Aluminum Powder) and FP (animal protein foaming agent) are lower than that of light-weight foamed concrete using AES (alkyl ether lactic acid ester). Lightweight foamed concrete using AES and FP satisfied fire performance requirements of two hours at a foam ratio 50, 100. Lightweight foamed concrete using AP satisfied fire performance requirements of two hours at AP ratio 0.1, 0.15. The insulation properties were better in closed pore foamed concrete by made AP, FP than with open pore foamed concrete made using AES.

• Journal of Bio-Environment Control
• /
• v.14 no.2
• /
• pp.95-105
• /
• 2005

This study was carried out to file up using effect and requirement of energy for environmental design data of Pleurotus eryngii growing houses. Heating and cooling Degree-Hour (D-H) were calculated and compared for. some Pleurotus eryngii growing houses of sandwich-panel (permanent) o. arch-roofed(simple) type structures modified and suggested through field survey and analysis. Also thermal resistance (R-value) was calculated for the heat insulating and covering materials of the permanent and simple-type, which were made of polyurethane or polystyrene panel and $7\~8$ layers heat conservation cover wall. The variations of heating and cooling D-H simulated for Jinju area was nearly linearly proportional to the setting inside temperatures. The variations of cooling D-H was much more sensitive than those of heating D-H. Therefore, it was expected that the variations of required energy in accordance with setting temperature or actual temperature maintained inside of the cultivation house could be estimated and also the estimated results of heating and cooling D-H could be effectively used far the verification of environmental simulation as well as for the calculation of required energy amounts. When the cultivation floor areas are all equal, panel type houses to be constructed by various combinations of materials were found to by far more effective than simple type pipe house in the aspect of energy conservation maintenance except some additional cost invested initially. And also the energy effectiveness of multi-span house compared to single span together with the prediction of energy requirement depending on the level insulated for the wall and roof area could be estimated. Additionally, structural as well as environmental optimizations are expected to be possible by calculating periodical and/or seasonal energy requirements for those various combinations of insulation level and different climate conditions, etc.

• Journal of Mushroom
• /
• v.16 no.3
• /
• pp.155-161
• /
• 2018

In this study, we analyze the growth environment using smart farm technology in order to develop the optimal growth model for the precision cultivation of the bottle-grown oyster mushroom 'Suhan'. Experimental farmers used $88m^2$ of bed area, 2 rows and 5 columns of shelf shape, 5 hp refrigerator, 100T of sandwich panel for insulation, 2 ultrasonic humidifiers, 12 kW of heating, and 5,000 bottles for cultivation. Data on parameters such as temperature, humidity, carbon dioxide concentration, and illumination, which directly affect mushroom growth, were collected from the environmental sensor part installed at the oyster mushroom cultivator and analyzed. It was found that the initial temperature at the time of granulation was $22^{\circ}C$ after the scraping, and the mushroom was produced and maintained at about $25^{\circ}C$ until the bottle was flipped. On fruiting body formation, mushrooms were harvested while maintaining the temperature between $13^{\circ}C$ and $15^{\circ}C$. Humidity was approximately 100% throughout the growth stage. Carbon dioxide concentration gradually increased until 3 days after the beginning of cultivation, and then increased rapidly to approximately 2,600 ppm. From the 6th day, $CO_2$ concentration was gradually decreased through ventilation and maintained at 1,000 ppm during the harvest. Light was not provided at the initial stage of oyster mushroom cultivation. On the $3^{rd}$ and $4^{th}$ day, mushrooms were irradiated by 17 lux light. Subsequently, the light intensity was increased to 115-120 lux as the growth progressed. Fruiting body characteristics of 'Suhan' cultivated in a farmhouse were as follows: Pileus diameter was 30.9 mm and thickness was 4.5 mm; stipe thickness was 11.0 mm and length was 76.0 mm; stipe and pileus hardness was 0.8 g/mm and 2.8 g/mm, respectively; L values of the stipe and pileus were 79.9 and 52.3, respectively. The fruiting body yield was 160.2 g/850 ml, and the individual weight was 12.8 g/10 unit.

• Journal of Mushroom
• /
• v.17 no.4
• /
• pp.197-204
• /
• 2019

In this study, smart farm technology was used by farmers cultivating 'CHIKUMASSHU T-011' in order to develop an optimal growth model for the precision cultivation of bottle-grown winter mushroom and the results of the same are mentioned herein. Farmers participating in the experiment used 60 ㎡ of bed area with 4 rows and 13 columns of shelf shape, 20 horsepower refrigerator, 100T of sandwich panel for insulation, 6 ultrasonic humidifiers, 12 kW of heating, and 20,000 bottles of Flammulina velutipes mushroom spores. The temperature, humidity, and carbon dioxide concentrations, which directly affect the growth of the mushroom, were collected and analyzed from the environmental sensors installed at the winter mushroom cultivation area. The initial temperature was found to be 14.5℃, which was maintained at 14℃ to 15℃ until the 10th day. In the restriction phase, the initial temperature was 4℃ and was maintained between 2℃ and 3℃ until the 15th day, while during the growth phase, it was maintained between 7.5℃ to 9.5℃. Analysis of the humidity data revealed initial humidity to be 100%, which varied between 88% to 98% during primordia formation period. The humidity remained between 77% to 96% until the 15th day, in the restriction phase and between 75% to 83% during the growth phase. The initial carbon dioxide concentration was 3,500 ppm and varied between 3,500 ppm to 6,000 ppm during primordia formation period and was maintained at 6,000 ppm until the 15th day. During the growth phase, the carbon dioxide concentration was found to be over 6,000 ppm. Fruiting body characteristics of 'CHIKUMASSHU T-011' cultivated in the farmhouse were as follows: Pileus diameter of 7.5 mm and thickness of 4.1 mm, stipe thickness of 3.3 mm, and length of 154.2 mm. The number of valid fruiting bodies was 1,048 unit per 1,400 mL bottle, and the individual weight was 0.71 g per unit. The yield of fruiting bodies was 402.8 g per 1,400 mL bottle.