• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.167-172
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• 1998

The purpose of this study is recycling of ready mixed concrete sludge as artificial aggregate by product technique of artificial aggregate in the normal temerature. For the qulity test of artificial aggregate using ready mixed concrete sludge, it is tested in the various aspect. Therefor, Quality of artificil aggregate is suitable as coarse aggregate except absoption, abrasion. For the application of aggregate in cement concrete, Coarse aggregate are replaced with artificial aggregate using ready mixed concrete sludge 100% of volume. The results of test shown that the artificial aggregate using ready mixed concrete sludge could be used replacement of coarse aggregate in cement concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.327-328
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• 2021

In the manufacturing process of ready-mixed concrete, quantity management directly affects the workability and strength of concrete. Therefore, water quantity is the most important management factor for water quality control of ready-mixed concrete. It can be said that the number of unit water in the mix design, the water quantity due to the surface water contained in the aggregate used, and the water quantity taking into account the concentration of sludge contained in the recycling water when using the recycling water are factors that affect the quantity management of ready-mixed concrete. In this study, as a stable quality control method of ready-mixed concrete, a quantity management method by aggregate surface water and a sludge concentration management method according to the use of recycling water were proposed. Thus, we tried to suggest an efficient quantity management method for stabilizing the quality of ready-mixed concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.72-73
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• 2013

In this paper, types of ready mixed concrete in construction site supported by different company has been researched. The practicability of the commercial available ready mixed concrete has been tested, and the standard deviation has been modified from Vc=Vo+3б to Vc=Vo+1.73б. Unnecessary premium rate has been cut and economical efficiency of the ready mixed concrete has been improved.

• Computers and Concrete
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• v.21 no.2
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• pp.139-147
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• 2018

Due to enhanced construction requirement, ready mixed concrete are being popular day by day. The current study aimed to develop ready mixed concrete using GBFS contained cement and determine its properties of fresh and hardened states. A real scale experiment was set up in a ready mixed plant for measuring workability and compressive strength. The workability was tested after mixing (within 5 minutes), 30, 60, 90, 120 and 150 minutes of the running of bulk carrier. The ready mixed carrier employed spinning motion i.e., rotating around its axis with 20 RPM and running on road with 1km/h speed. The mixing ratio of cement: sand:gravel, water to cement ratio, super plasticizer were, 1:1.73:2.47, 0.40 and 6% of cement, respectively. The chemical composition of raw material was determined using XRF and the properties of cements were measured according to ASTM standards. The experimental results confirm that the cement with composition of 6.89% of GBFS, 4% of Gypsum and 89.11% of clinker showed the good compressive strength and workability of concrete after 150 minutes of the spinning motion in bulk carrier.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.979-984
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• 2003

Quality control of ready-mixed concrete is most important in the production step because, the performance of hardened concrete is revealed due to ready-mixed concrete. Hardened concrete has several properties physically. Above all things compressive strength of concrete has a greate effect in the design of structures, analysis, and durability. Compressive strength is simple predicted by w/c up to date, but there are some limits because different compressive strengths can be revealed in the same w/c. Therefore this study contributes to the quality control of ready-mixed concrete through statistical analysis for the relation between mix factors in mix design and compressive strength, predictable equation for compressive strength.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.647-650
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• 2001

The purpose of this study was the influence of cold weather ready mixed concrete quality according to needs of customer were investigated by measurements of slump, air content, temperature and compressive strength. As a results, cold weather ready mixed concrete using high standard admixtures, high early strength admixtures and cold weather concrete plant were similarly to slump, air content, temperature and compressive strength.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05a
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• pp.606-609
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• 2006

In this study, it was selected that in order to make an investigation into the status of the unit water content control of the ready-mixed concrete plants in the country, Capacitance Measurement Method out of various methods which are able to gauge the amount of unit water content in fresh concrete. Then, it were estimated that the quantity of unit water in fresh concrete and the technical standard of every mixture design of the six ready-mixed concrete plants chosen at random in the country. Finally, based on this study, it was proposed as fundamental data to utilize measurement techniques of the quantity of unit water for the quality control of the ready-mixed concrete in construction field.

• Proceedings of the Korea Concrete Institute Conference
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• 1992.10a
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• pp.54-57
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• 1992

This report presents the survey findings on the proportioning of ready mixed, concrete mixtures. According to this report, the W/C ratio and S/A ratio, based upon the type 25-210-12, in mix proportion of ready mixed concrete are 53% and 45% respectively. The problems to be improved, coming out in this study, are (1)using the adequate quantity of cement (2) alternation of mix design cope with the change of kinds of aggregates (3)large standard error in the mix proportion.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.337-340
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• 2008

As the Ready-mixed Shotcrete using Powdered Polymer Dispersion, Shotcrete Matrix as totally shotcrete gel that a part of second binder in Shotcrete materials is dense. Also, Ready-mixed Shotcrete is showed the decreasing Rebound and rising Durability. Therefore, it is possible that Ready-mixed Shotcrete for High-Strength and High-Waterproof can apply to the Powdered Polymer Dispersion.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.11a
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• pp.11-12
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• 2017

The properties of concrete produced by ready mixed concrete company in Busan were tested. Because the concrete was mixed with blast furnace slag and fly ash, the compressive strength and chloride ion diffusion coefficient were lower than OPC concrete even though the specified concrete strength was same. If the durability about salt attack were satisfied, the concrete of lower specified concrete strength would be adopted to concrete mixing design.