• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.375-376
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• 2010

This study is shown the chemical characteristics by SEM and XRD for the Light-weight Foamed Concrete according to replacement ratio of WCP and the autoclave curing time. From the SEM of the Light-weight Foamed Concrete after hydrothermal raction, regardless of replacement ratio of WCP and the autoclave curing time, forms the crystal hydrates having various shapes such as board and fiber etc is generated. From the XRD, it seems that the tobermorite hydrate is originated from crystalized quartz.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.649-652
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• 2008

Glass is often recycled. In order to recycle, glass is crushed and ground. During this process, glass powder is generated. Most of this scrap glass powder is disposed in landfills. The glass powder, consisting of 73% SiO$_2$ and 16% Al$_2$O$_3$, is richer in components necessary for polymerization than fly ash. In this study, the fluidity and compressive strength of cement zero mortar were investigated, where cement zero mortar was prepared by mixing 5$\sim$15% of glass powder with 100% fly ash mortar. Result of flow test concluded that workability was not affected by adding the powder. After aging for 28 days, the compressive strength increased by approximately 6% with 5% addition of scrap glass powder. With 10% addition, the strength remained the same. In case of 15% addition, the compressive strength decreased by approximately 6%. To summarize the results, 5$\sim$10% addition of scrap glass powder is considered to be most appropriate.

• International Journal of Highway Engineering
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• v.13 no.2
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• pp.85-93
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• 2011

This study experimented to evaluate the environment friendly high performance ternary cement concrete deck overlay pavement using mineral admixture such as fly ash and ground granulated blast-furnace slag. It was measured to find best binder mixing according to replacement rate of mineral admixture with compressive strength and flexural strength. After finding best binder, it is also experimented to evaluate durability on chloride penetration resistance, freezing- thawing resistance, scaling resistance of deicing chemicals, abrasion resistance, alkali-silica reactivity test and bonded environment friendly high performance ternary cement concrete deck overlay pavement experimented to evaluate bonded old deck and new concrete overlay pavement using special polymer cement mortar. In additions, bonded environment friendly high performance ternary cement concrete deck overlay pavement by experimental construction was evaluated at interchange bridge of North Yeoju. Result, examination was indicated better binding with binder replacement of cement 70%, ground granulated blast-furnace slag 15% and fly ash 15%. And special polymer cement mortar used in old deck and new overlay concrete was indicated better bonding both laboratory and construction.

• Resources Recycling
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• v.18 no.3
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• pp.3-10
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• 2009

This paper will introduce the study which is the solidification and reduction of $CO_2$ green house gas, by using inorganic industrial wastes such like waste cement, steel making slag, incineration ash and so on. These inorganic wastes contain a large quantity of CaO content in common, which is easily reacted with CaO resulting in formation of $CaCO_3$. It will be suggested in this study that the necessary of the reduction and solidification of $CO_2$ gas with using industrial inorganic wastes is for building the Korea carbon storage model in this study.

• Journal of the Korea Institute of Building Construction
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• v.24 no.2
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• pp.181-191
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• 2024

In the realm of cement manufacturing, concerted efforts are underway to mitigate the emission of greenhouse gases. A significant portion, approximately 60%, of these emissions during the cement clinker sintering process is attributed to the decarbonation of limestone, which serves as a fundamental ingredient in cement production. Prompted by these environmental concerns, there is an active pursuit of alternative technologies and admixtures for cement that can substitute for limestone. Concurrently, initiatives are being explored to harness technology within the cement industry for the capture of carbon dioxide from industrial emissions, facilitating its conversion into carbonate minerals via chemical processes. Parallel to these technological advances, economic growth has precipitated a surge in construction activities, culminating in a steady escalation of construction waste, notably waste concrete. This study is anchored in the innovative production of calcium silicate cement clinkers, utilizing finely powdered waste concrete, followed by a thorough analysis of their mineral phases. Through X-ray diffraction(XRD) analysis, it was observed that increasing the substitution level of waste concrete powder and the molar ratio of SiO₂ to (CaO+SiO₂) leads to a decrease in Belite and γ-Belite, whereas minerals associated with carbonation, such as wollastonite and rankinite, exhibited an upsurge. Furthermore, the formation of gehlenite in cement clinkers, especially at higher substitution levels of waste concrete powder and the aforementioned molar ratio, is attributed to a synthetic reaction with Al₂O₃ present in the waste concrete powder. Analysis of free-CaO content revealed a decrement with increasing substitution rate of waste concrete powder and the molar ratio of SiO₂/(CaO+SiO₂). The outcomes of this study substantiate the viability of fabricating calcium silicate cement clinkers employing waste concrete powder.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.278-279
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• 2014

This study was performed an evaluation of mechanical properties of reactive powder concrete using copper slag. So, various RPC containing copper slag were made by replacement ratio of copper slag and different the curing condition and their mechanical properties were investigated. From the experimental results, slump flow using copper slag tends to increase with replacement ratio. And also, 30% of copper slag with quartz sand was found to have a compressive strength superior to that of plain.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.3
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• pp.356-363
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• 2017

Blast furnace slag(BFS) is a by-product generated during the manufacture of pig ion, and is divided into water-cooled slag(WS) and air-cooled slag(AS) by the coking method of BFS. In this study, concrete specimens with ternary binders were produced at the various replacement levels of cement by AS. Various mechanical properties of concrete, such as compressive and split tensile strengths, absorption and water permeable pore, were measured. In addition, the chloride ions penetration resistance and carbonation resistance were tested to evaluate the durability of concrete incorporating AS. The experimental data indicated that the use of AS up to a maximum of 10% replacement level enhanced the concrete performance. However, a higher replacement of AS exhibited poor mechanical properties and concrete durability.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.74-75
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• 2013

The paper study on the mechanical properties of reactive powder concrete using copper slag. A change in the replacement ratio s of copper slag was measured compressive strength and slump flow. As a results, slump flow using copper slag tend to increase slump flow with replacement ratio. As the concrete with a replacement ratio of copper slag up to 30% was found to have a compressive strength superior to that of plain.

• Journal of the Korea Institute of Building Construction
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• v.16 no.4
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• pp.321-329
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• 2016

The use of ternary blended cement consisting of Portland cement, granulated blast-furnace slag (GGBFS) and fly ash has been on the rise to improve marine concrete structure's resistance to chloride attack. Therefore, this study attempted to investigate changes in chloride attack resistibility of concrete through NT Build 492-based chloride migration experiments and test of concrete's ability to resist chloride ion penetration under ASTM C 1202(KS F 2271) when 1.5-2.0% of alkali-sulfate activator (modified alkali sulfate type) was added to the ternary blended cement mixtures (40% ordinary Portland cement + 40% GGBFS + 20% fly ash). Then, the results found the followings: Even though the slump for the plain concrete slightly declined depending on the use of the alkali-sulfate activator, compressive strength from day 2 to day 7 improved by 17-42%. In addition, the coefficient from non-steady-state migration experiments for the plain concrete measured at day 28 decreased by 36-56% depending on the use of alkali-sulfate. Furthermore, total charge passed according to the test for electrical indication of concrete's ability to resist chloride ion penetration decreased by 33-62% at day 7 and by 31-48% at day 28. As confirmed in previous studies, reactivity in the GGBFS and fly ash improved because of alkali activation. As a result, concrete strength increased due to reduced total porosity.

• Journal of the Korean Recycled Construction Resources Institute
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• v.10 no.1
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• pp.48-55
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• 2022

This study uses the recovered water as mixing water and artificial lightweight aggregate pre-wetting water as part of a study to increase the recycling rate and reduce greenhouse gas of the ready-mixed concrete recovered during the concrete transport process, and cement fine powder of blast furnace slag(BFS) and fly ash(FA). The engineering characteristics of the three-component lightweight aggregate mortar used as a substitute were reviewed. For this purpose, the flow, dry unit mass, compressive strength, drying shrinkage, neutralization depth, and chloride ion penetration resistance of the three-component lightweight aggregate mortar were measured. When used together with the formulation, when 15 % of BFS and 5 % of FA were used, it was found to be positive in improving the compressive strength and durability of the mortar.