• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.1
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• pp.200-207
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• 2019

Cement is one of the most commonly used materials in the construction and civil engineering industry. However, emissions of carbon dioxide generated during the production of cement have been linked to climate change and environment pollutants. In order to replace cement, many studies have been actively performed research to utilizing Blast Furnace Slag(BFS), which is a byproduct of the steel industry. This study aims to investigate the physiochemical properties of the BFS powder based grout to determine whether it can be used as an environment-friendly grout material. As a fine powder, BSF can be used instead of cement grout due to its potential hydraulic property. BSF has also been known for its ability to strengthen materials long-term and to densify the internal structure of concrete. In order to investigate the physicochemical properties of the BFS powder based grout as a grout material, in this study assessment tests were performed through a gel-time measurement, uniaxial compressive strength, and chemical resistance tests, and heavy-metal leaching test. Characteristics and advantages of the slag were studied by comparing slag and cement in various methods.

• International Journal of Concrete Structures and Materials
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• v.8 no.2
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• pp.157-164
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• 2014

Ground granulated blast-furnace slag (GGBS) is a green construction material used to produce durable concrete. The secondary pozzolanic reactions can result in reduced pore connectivity; therefore, replacing partial amount of Portland cement (PC) with GGBS can significantly reduce the risk of sulfate attack, alkali-silica reactions and chloride penetration. However, it may also reduce the concrete resistance against carbonation. Due to the time consuming process of concrete carbonation, many researchers have used accelerated carbonation test to shorten the experimental time. However, there are always some uncertainties in the accelerated carbonation test results. Most importantly, the moisture content and moisture profile of the concrete before the carbonation test can significantly affect the test results. In this work, more than 200 samples with various water-cementitious material ratios and various replacement percentages of GGBS were cast. The compressive strength, electrical resistivity, chloride permeability and carbonation tests were conducted. The moisture loss and microstructure of concrete were studied. The partial replacement of PC with GGBS produced considerable improvement on various properties of concrete.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2012.05a
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• pp.287-288
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• 2012

In this study, Analyzed the effect of the change in RFA and RCA substitution rate on the concrete containing BS bonding materials but no cement. The findings are as follows. First, the fresh concrete has less slump value and air contents as more RFA and RCA is used. In case of hardened concrete, as more RFA and RCA are used, the higher the compressive strength of concrete becomes. Especially, the compressive strength of concrete which used recycled aggregates only is found to be 2.2 times as high as that of concrete using natural fine and coarse aggregates only. But if the concrete is to be used as the structural concrete having the compressive strength of 13.8 MPa, the alkaline materials and some cement are required to be added.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.196-197
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• 2013

This study is the experiment for manufacturing the Lightweight non-cement matrix based on the Blast furnace slag. And, the matrix was manufactured matrix by generating the bubble just by the reaction of KOH that is the alkali accelerator and paper ash, instead of the general foaming agent, that is the waste managed of incineration the pulp sludge generated in the process of manufacturing the paper. Consequently, the density according to the addition rate of KOH represented the tendency to increase. And it showed up that density of the matrix adding KOH 22.5% was the lowest. As to the strength test result, strength following addition rate of KOH increased. Since the bubble is generated in the reaction of KOH and paper ash, this shows the very low intensity but it is determined to be the result that the amount of vacant space is decreased because the bubble generated in the mixture process comes up as the specific gravity difference.

• Advances in concrete construction
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• v.13 no.3
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• pp.233-242
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• 2022

An attempt is made to develop an eco-friendly concrete with ground granulated blast furnace slag (GGBS) and pond ash as partial replacement materials for cement and fine aggregate, respectively without compromising the strength and durability. Sixteen concrete mixes were developed by replacing cement and fine aggregate by GGBS and pond ash, respectively in stages of 10%. The maximum replacement levels of cement and fine aggregates were 50% and 30% respectively. Experimental results revealed that the optimum percentage of GGBS and pond ash replacement levels were 30% and 20% respectively. The optimized mix was used further to study the flexural behavior and durability properties. Reinforced Concrete (RC) beams were cast and tested under a four-point bending configuration. Also, the specimens prepared from the optimized mix were subjected to alternate wet and dry cycles of acid (3.5% HCl and H₂SO₄) and sulphate (10% MgSO₄) solutions. Results show that the optimized concrete mix with GGBS and pond ash had a negligible weight loss and strength reduction.

• Resources Recycling
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• v.22 no.6
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• pp.12-18
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• 2013

In this Study, it was fabricated that shrinkage reducing agent and mortar used $C_{12}A_7$-based slag enhanced the shrinkage reduction and compressive strength. To reduce cement content, setting time, flow and compressive strength of mortar with varying content of fly ash and blast furnace slag were experimented. The flow increased and setting time delayed as the increase of fly ash and blast furnace slag content. And early strength was lower and long age strength was higher than that of mortar with low content of admixture.

• Journal of the Korea Institute of Building Construction
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• v.13 no.6
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• pp.602-608
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• 2013

The aim of this study is to investigate experimentally the effect of the combination of fine particle cement with high Blaine fineness (FC) and recycled aggregates on the engineering properties and micro structure of high volume blast furnace slag (BS) concrete with 75% BS and 21 MPa. FC manufactured by particle classification at the plant with Blaine fineness of more than $7000cm^2/g$ was used as additional alkali activator for high volume blast furnace slag concrete made with recycled fine and coarse aggregates. FC was replaced by 15, 20 and 25% OPC. Test results showed that the incorporation of FC resulted in an increase in the compressive strength compared to BS concrete without FC by as much as 30% due to accelerated hydration and associated latent hydraulic reaction. It was found that the use of FC and recycled aggregates played an important role in activating BS for high volume BS concrete by offering sufficient alkali.

• Korean Journal of Agricultural Science
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• v.26 no.2
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• pp.49-55
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• 1999

This study is performed to evaluate the properties of permeable polymer concrete with blast furnace slag and fly ash. The following conclusions are drawn: 1. The highest strength is achieved by 50% filled blast furnace slag powder and fly ash permeable polymer concrete, it is increased 36% by compressive strength and 217% by bending strength than that of the normal cement concrete, respectively. 2. The static modulus of elasticity is in the range of $100{\times}10^3{\sim}130{\times}10^3kgf/cm^2$, which is approximately 43~51% of that of the normal cement concrete. 3. The dynamic modulus of elasticity is in the range of $102{\times}10^3{\sim}130{\times}10^3kgf/cm^2$, which is approximately less compared to that of the normal cement concrete. The highest dynamic modulus is showed by 50% filled blast furnace slag powder and fly ash permeable polymer concrete. The dynamic modulus of elasticity are increased approximately 0~4% than that of the static modulus. 4. The water permeability is in the range of $4.612{\sim}5.913l/cm^2/h$, and it is largely dependent upon the mix design.

• Journal of the Korea Institute of Building Construction
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• v.15 no.6
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• pp.597-605
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• 2015

The method of concrete mix design used in this study aims to achieve the identical specified design strength, applying different types and replacement ratio of mineral admixtures and afterwards, fire tests were conducted using the standard time-temperature curve specified in the ASTM E119 to identify the influences of the types of mineral admixtures on the fire resistance performance of high strength concrete(HSC). The least spalling was observed in the test specimen containing blast furnace slag as a partial replacement of cement, while the most significant spalling phenomena were observed in the blast furnace slag test specimen that silica-fume was added in. In particular, the reasonable volume of spalling was observed when solely replaced by silica fume. However, the influence of the cement replacement by silica fume and blast furnace slag on the increases of spalling can be explained through blocked pores by the fine particles of silica fume, leading to decreases in permeability.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.3
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• pp.69-78
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• 2011

As recent concrete products changed to pursue high class, high quality, and high strength, as translucent concrete was developed to meet esthetic effects and exhibition purpose of structures. This study aims at introducing fabrication methods of various shapes of translucent concrete and evaluating feasibility of using mineral admixture such as fly ash, ground granulated blast furnace slag and granulated glass throughout experimental tests. As the result, it was found that compressive strength of translucent concrete block at 28 days is 32.2MPa and higher elastic modulus and Poisson's ratio than ordinary concrete block, which means that translucent concrete is widely applicable to structural purpose. Application of fly ash as a replacement of cement showed lower strength of 85 to 96% than Portland cement. In the meanwhile, ground granulated blast furnace slag showed 82 to 96% depending on the amount of replacement. The use of granulated glass as replacement of optical fiber was not applicable due to invisibility of light in concrete.