• Journal of the Korean Institute of Electrical and Electronic Material Engineers
• /
• v.11 no.7
• /
• pp.502-507
• /
• 1998

The purpose of this study is to investigate the breakdown properties in joint interface of power cables with heat treatment. The specimens have the structure of XLPE/EPDM interface like the joint of distribution power cable. The breakdown characteristics of the SLPE/EPDM joint were studied with crosslinking by=products. AC breakdown voltages were measured with heat treatment time and interfacial materials and crosslinking by-products as testing factors. This study has shown that crosslinking by-product gases play an important role at the insulation properties of cable joints by heating. The dielectric strength shows the lowest values at 4 hours heat treatment. The AC breakdown strength in the untreated sample was increased with heat treatment time.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2013.05a
• /
• pp.318-320
• /
• 2013

The spherical bead manufactured by rapidly cooling process shows high density of 3.64g/㎤, high unit volume weight of 2.6kg/l, and high solid volume of 71%. When it applies to the grouter, it is possible to obtain even high fluidity with only a small amount. This study, focusing the grouter using a rapidly-cooled electric arc furnace oxidizing slag(RC-EAFS), deals with the properties of flow and setting time in fresh state, compressive strength and length variation at 1, 3, 7 and 28 curing day in hardened state. As the results, even though the grouter with RC-EAFS shows comparative low strength, it will be possible to development the competitive product due to the properties of increasing flow and low cost.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2017.05a
• /
• pp.206-207
• /
• 2017

We investigated the fluidity and compressive strength properties of mortar by Grading Variation of Ferro-Nickel Slag Sand in order to improve the utilization of ferro-nickel which is the by-product produced by making stainless steel, in the construction industry.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2012.11a
• /
• pp.35-38
• /
• 2012

Spacers which we have studied is the secondary product of the concrete to apply on concrete structure. It is needed to secure equal or greater performance than structural concrete that it is applied. There is a tendency that concrete structures are strengthened more and more. Therefore, designed set up position of reinforcement is used more and more, so it is needed increasingly high strength spacer. We have been doing a series of research to develop the different typed high strength spacer having crack resistance during constructing. The bearing load of different type spacer shows approximately 35% lower load than those in the general spacers.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2009.05a
• /
• pp.403-404
• /
• 2009

This study has investigated application of the industrial by-product of reject ash and recycled fine aggregate to consider the economical issue to high flowing CLSM(controled low-strength material). But this high flowing CLSM is required more binder, so it has been estimated the influence of reject ash content, use of recycled fine aggregate and crushed sand, and air content about properties of CLSM.

• Proceedings of the Korean Society For Composite Materials Conference
• /
• 2003.10a
• /
• pp.203-206
• /
• 2003

Using composite materials for the carbody of tilting train has many advantages such as manufacturing variety, specific high-strength ＆ stiffness characteristics, and long-life durability, but the strongest advantage could be the possibility of lightweight product. In the leading countries, the composite materials are used for the material fur drivers'cabs, interior/exterior equipments for railway train, and it is now developing the composite materials applied for the train carbody structure. In this paper, we conducted the evaluation of structural stability for the aluminum and composite carbody of the Korean Tilting Train express(TTX) with the service speed of 180km/h.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2016.05a
• /
• pp.141-142
• /
• 2016

This study was examine the possibility and mechanical properties to adsorption and decrease of caused interior Radon using performance superior cation-exchange to take advantage of the building. Radon absorption type Matrix using the magnesium oxide and vermiculite was experiment to product that vermiculite added Vermiculite to 10% of magnesium oxide and magnesium chloride was fixed to 25%. W/B was carried out in 45, 50, 55, 60 (wt,%).

• Proceedings of the Korea Concrete Institute Conference
• /
• 2006.11a
• /
• pp.441-444
• /
• 2006

Extrusion molding concrete panel is cured two times, that is the steam curing at atmospheric pressure and a high-pressure steam curing(autoclaving). Steam curing at atmospheric pressure is done before autoclaving and to acquire the proper strength for treat in process. Though this curing is the important factor on the quality of product and the speed in manufacturing process, it was not evaluated properly so far. Because of ignorance about curing, some engineers even think that the dry curing is better than the steam curing. This study is to investigate the properties of specimen according to variation of curing conditions in the coring chamber such as laboratory scale, pilot plant, and commercial plant. As estimating, in case of steam curing at atmospheric pressure to make extrusion molding concrete panel, moisture curing is better than dry curing and the desirable maximum temperature in curing chamber is about $50^{\circ}C$.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2002.10a
• /
• pp.293-298
• /
• 2002

Recycling of coal combustion by-product(Ash) are becoming more improtant in the utilization business as a result of the increased use of NOx reduction technologies at coal-fired power plants. current disposal methods of these by-products create not only a loss of profit for the power industry, but also environmental concerns that breed negative public opinion. This research made concrete crecast block using coal ash artificial aggregate for environmental-friendly products and compared strength special quality of this block with existent common use brick and analyzed application possibility in situ with a reserve experiment that measured strength property and manufactured method to handle coal ash produced in Bo-ryung thermoelectric power plant.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2004.05a
• /
• pp.180-183
• /
• 2004

In general, the polymer is mainly used with the cement mortar with various admixtures for concrete repair. The properties of cement-polymer mortar was studied by the cement-polymer ratio only and ignored any influence of admixtures in the mortar. Therefore in this study, the test is carried out with 2 product of polymers(the same type produced by different companies) and various admixtures. It is found that the same type of polymers produced by different companies affect the properties of fresh and hardened concrete. As increasing the polymer proportion in mortar, the compressive strength and flexural strength are increased, and also drying shrinkages is increased.