• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.233-236
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• 1999

In this paper, we carried out fundamental experiments to use the steel manufacturing slag as a concrete aggregate. Generally there are two types of slag, the blast-furnace slag and the steel manufacturing slag. The latter is classified by the difference of manufacturing method of steel into the convertor slag and the electric-furnace slag. The steel manufacturing slag mainly contains SiO2 and CaO as the chmical composition. The reaction with water and a little of free CaO in the steel manufacturing slag makes the expansion of volume change. Therefore, we primarily investigated physical properties, expansion mechanism, pH value, aging effects and aging methods in the steel manufacturing slag. Then compressive strength of concrete with steel slag aggregate is measured.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.275-278
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• 2000

In this paper, we carried out fundamental experiments to use steel manufacturing slag as a concrete aggregate. Generally, there are two types of slag, the blast-furnace slag and the steel manufacturing slag. The latter is classified by the difference of manufacturing method of steel into the convertor slag and the electric-furnace slag. The steel manufacturing slag mainly contains $SiO_2$ and CaO as the chemical composition. The reaction with water and a little of free CaO in the steel manufacturing slag made the expansion of volume change, Therefore, we primarily investigated physical properties, expansion mechanism, pH value, aging effect and aging methods in the steel manufacturing slag, Then compressive strength of concrete with steel slag aggregate is measured.

• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.323-328
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• 1997

The strength of concrete depends on factors of materials, composition and manufacturing method. Among these factors, preparatory experiments are to consider and analyze the factors on compressive strength of ultra-high strength concrete according to types of aggregate, binder content, water-binder ratio, and curing methods. And the final experiment to develop the ultra-high strength over 3,000kgf/$\textrm{cm}^2$ is based on these preparatory experiments. As the result of this final expriment. We could manufacture the ultra-high strength concrete with a marvelous compressive strength concrete with a marvelous compressive strength of 3,116kgf/$\textrm{cm}^2$. This study is to compare and analyze the manufacturing system of ultra-high strength concrete of 3,116kgf/$\textrm{cm}^2$ compressive strength in the side of material development of construction industry.

• Proceedings of the Korea Concrete Institute Conference
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• 2004.05a
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• pp.364-367
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• 2004

The purpose of this study is to investigate quality of recycled fine aggregate manufactured by drying manufacturing system which is the manufacture method of high quality recycled fine aggregate, and to analyze on the fresh, hardened and durability properties of recycled concrete using it. Therefore it is to present the fundamental data for structural application of recycled concrete. The results of this study are as follows; Quality of recycled fine aggregate by drying manufacturing system is improved, and compressive and tensile strength of recycled concrete using high quality recycled fine aggregate are similar to those of normal concrete. But, durability such as carbonation, salt damage and dry shrinkage show decreased somewhat.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.33-36
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• 1998

Generally, the base concrete for manufacturing the flowing concrete has to increase the fine aggregate content or adjust the fines content prevent the concrete from segeration, However, it may not only increase the cost, but cause the inconvenience in production of base concrete. In this paper, the experiments is performed on the superplasticizer which is used for base concrete by mixing viscosity agents and AE admixtures. According to the results, it shows that it is possible to manufacture a flowing, non segregation, high durability and economical concrete in the field without increasing the fine aggregate content of base concrete, when the superplasticizer are mixed with viscosity agents and AE admixtures in an appropriate proportion.

• Journal of Korean Society for Atmospheric Environment
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• v.30 no.1
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• pp.37-47
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• 2014

In this study, field measurement was carried out for reasonable improvement of asphalt concrete manufacturing facilities' PM emissions estimation method. Through those, this study calculated PM emission factor and tried to estimate PM emissions from asphalt concrete manufacturing facilities suitable for domestic characteristics. As a result, the efficiency of the PM control device was measured as 99.9%. Using this, uncontrolled PM emission factor was calculated. PM emission factor was calculated 10.97 kg/ton at 23 asphalt concrete manufacturing facilities of 22 workplaces. The PM current emission factor of the US Environment Protection Agency (EPA) is 14.4 kg/ton, the factor calculated from this study is about 24% lower than the EPA standard.

• Journal of the Korean Society of Manufacturing Process Engineers
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• v.19 no.12
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• pp.34-41
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• 2020

Ready-mixed concrete is unconsolidated concrete typically transported to construction sites by using mixer trucks. A proper rotation of concrete is necessary to prevent its solidification in mixer trucks during transport: in accordance with the manufacturing method and quality inspection prescribed in KSF4009, this movement is maintained after the manufacturing of concrete in professional production plants and the addition of water, solid materials, and admixtures. Unfortunately, mixer truck parts wear out over long periods of time. In order to improve the wear resistance of the main part of mixer trucks, we used a steel plate with good wear resistance or partially added a reinforcement plate. In this study, we first tested the properties of concrete (as required for the DEM), and then carried out mixing and discharge simulations to define the actual operating conditions of mixer trucks. For each condition, we calculated the amount and location of wear. The reliability of our results was finally verified by comparing them with the measurement values. Overall, this study provided basic data for an optimal design of mixer trucks: one that would reduce the vehicles' weight and production costs.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.05a
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• pp.187-188
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• 2016

The purpose of this study is to develop a method of evaluating eco-efficiency of concrete based on environmental load emission, manufacturing cost, and durability in the concrete production process. Eco-efficiency is an advanced concept used to evaluate eco-friendliness of concrete. This technique intends to produce environment-friendly and highly durable concrete while minimizing environmental load on the ecosystem and manufacturing cost based on the results of service life assessment on concrete. This technique can be utilized to efficiently evaluate sustainability of concrete and find methods to improve it. Furthermore, the vision of this study is to contribute to implementation of environment-friendly concrete and construction industry.

• Magazine of the Korea Concrete Institute
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• v.3 no.4
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• pp.44-52
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• 1991

• Magazine of the Korea Concrete Institute
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• v.5 no.3
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• pp.10-18
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• 1993