• 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

• Magazine of the Korea Concrete Institute
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• v.5 no.3
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• pp.19-30
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• 1993

• Magazine of the Korea Concrete Institute
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• v.5 no.3
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• pp.45-54
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• 1993

• Magazine of the Korea Concrete Institute
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• v.5 no.3
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• pp.55-62
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• 1993

• Magazine of the Korea Concrete Institute
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• v.28 no.4
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• pp.20-25
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• 2016

• Magazine of the Korea Concrete Institute
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• v.9 no.2
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• pp.23-29
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• 1997

• Journal of the Korea Institute of Building Construction
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• v.19 no.4
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• pp.307-312
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• 2019

Sludge generated in the production of ready-mixed concrete is classified as waste and processed at a high cost. In particular, small and medium-sized ready-mix manufacturer are burdened with such costs, and some companies are illegally processing them. Therefore, the purpose of this study is to suggest a method for recycled remicon sludge as a concrete block composition. When the remicon sludge is simply dried, the residual chemical admixture and ettringitee contained in the sludge are present, so that the compressive strength of the concrete block and the compressive strength after freezing and thawing are largely deteriorated to meet the quality standards of the concrete shore and retaining wall block It was not possible to do. As a method for satisfying the physical performance, it was found that the remicon sludge was calcined at a high temperature of about $900^{\circ}C$. to decompose ettringite and residual chemical admixture and then used it.

• Journal of the Korea institute for structural maintenance and inspection
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• v.3 no.1
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• pp.163-169
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• 1999

The object of this study is to compare properties of massive fly-ash concrete with plain concrete. Two concrete mixtures comprising two batch each $1.0m^3$ in volume, were made from ready mixed concrete batch plant. The water-to-cementitious materials ratio was kept constant at 51.4%. Therefore, massive concrete specimen($W800{\times}D800{\times}H800mm$) was cast from ready mixed concrete to analyze history of temperature and core strength properties. Bleeding, time of slump loss and time of setting of the fresh concrete were measured. In order to estimate the properties of massive fly-ash concrete in hardened concrete, non-destructive tests such as rebound hardness, ultrasonic pulse velocity and maturity were performed and analyzed.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.507-512
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• 2002

In road pavements, it is known that cement concrete pavement has superior durability. But in repairing pavement, cement concrete pavement is not usually applied because of the length of time while the road is interrupted when using Ordinary and Rapid-hardening Portland Cement. And Super High Early Strength Cement and Ultra Super High Early Strength Cement are not favorable for ready mixed concrete because of rapid setting time, high slump loss and other restrictions. We developed special cement developing 1 day strength of over 30.0N/$mm^2$ to open the road within 1 day and workable time is maintained over 1 hour so that it can be used as ready mixed concrete. We performed experimental overlay construction with concrete and evaluated the properties of the fresh and hardened concrete. The flexural strength was over 5.0N/$mm^2$ and the compressive strength was over 30N/$mm^2$ at 1 day. So it is thought that the road can be open to traffic within 1 day after placement.

• Computers and Concrete
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• v.21 no.5
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• pp.531-538
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• 2018

The slag through sieve #4 replaced the natural fine aggregate in different proportions (0-50%) to make ready-mixed soil and slag (RMSAS). The fresh properties studied, and the concrete specimens were produced to test the hardened properties at different ages. Results showed that the workability of RMSAS decreases when the replacement increases. The unit weight increases with the replacement. The setting time extends when the replacement decreases and shortens when the replacement increases. The compressive strength, ultrasonic pulse velocity and hammer rebound value increase with the replacement. However, the high-replacement results decrease because of the expansion factor at late age. Resistivity is close and less than $20k{\Omega}-cm$. After the industrial of steelmaking by-products are processed properly, they can be used in civil engineering, not only as a substitute for natural resources and to reduce costs, but also to provide environmental protection.