• Tunnel and Underground Space
• /
• v.27 no.5
• /
• pp.312-323
• /
• 2017

In this study, an influence of mixing ratio among firing oyster shell, non-firing oyster shell, magnetic separated converter steel slag and fly ash used as admixtures on strength properties of soil cement was evaluated by correlation analysis among compressive strength, deformation modulus and mixing ratio of admixtures. As a result, the strength of the specimens containing non-firing oyster shells was found to be larger than that of firing oyster shells, and it was confirmed that firing oyster shells could negatively affect the strength of soil cement specimens unlike previous studies. In addtion, there was a positive correlation between the ratio of magnetic separated converter slag and strength properties, so it is confirmed that it can be used as an admixture.

• Nuclear Engineering and Technology
• /
• v.56 no.7
• /
• pp.2828-2834
• /
• 2024

This research intends to recycle bone and incorporate it into concrete for radiation shielding application using Phy-X/PSD software. Cement, sand and granite were mixed in proportion of 0.5 kg:1 kg:1 kg to obtain sample A. Other concretes composing of cement, sand, granite and bone ash was in proportion 0.45 kg:1 kg:1 kg:0.05 kg, 0.1 kg:1 kg:1 kg:0.4 kg and 0.35 kg:1 kg:1 kg:0.15 kg to obtain samples B, C and D respectively. 0.5 water-to-cement (W/C) ratio was adopted throughout the mixes because the control mix contain the normal water quantity for normal hydration of cement. Replacing the bone ash for the cement in the fabricated concretes enhances their densities where the fabricated concretes' density decreased from 2.33 g/cm³ to 2.22 g/cm³ by raising the reinforcing bones fly ash concentration from 0 to 0.15 kg. Additionally, increasing the bones fly ash concentration within the fabricated concretes increases their linear attenuation coefficient (LAC) where the fabricated concretes' μ values at 0.662 MeV reach 0.181 cm^-1, 0.178 cm^-1, 0.174 cm^-1, and 0.171 cm^-1, respectively for concretes A, B, C, and D. The use of other local materials is recommended, as it improves waste management being the major aim of the sustainable development goal.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.7 no.1
• /
• pp.22-28
• /
• 2019

Cement is a basic material for the construction industry and it requires high temperature sintering when manufacturing cement. $CO_2$ emissions from raw materials and fuels are recognized as new environmental problems and efforts are underway to reduce them. Techniques for reducing $CO_2$ in concrete are also recommended to use blended cement such as blast furnace slag or fly ash. In addition, the construction waste generated in the dismantling of concrete structures is recognized as another environmental problem. Thus, various methods are being implemented to increase the recycling rate. The purpose of this study is to utilize the inorganic raw materials generated during the dismantling of the structure as a raw material for the low carbon type cement binder. Such as, waste concrete powder, waste cement block, waste clay brick and waste textile as raw materials for low carbon type cement binder. From the research results, low carbon type cement binder was manufactured from the raw material composition of waste concrete powder, waste cement block, waste clay brick and waste textile.

• Journal of the Korean Ceramic Society
• /
• v.53 no.3
• /
• pp.354-361
• /
• 2016

The purpose of this study was to prepare lightweight foamed concrete by mixing coal fly ash of circulating fluidized bed combustion(CFBC) with cement, and to develop uses for recycling by analyzing carbonation behavior resulting from a change in conditions for pressurized carbonation. For concrete, CFBC coal fly ash was mixed with Portland cement to the water-binder ratio of 0.5, and aging was applied at room temperature after 3 days of curing at $20^{\circ}C$, RH 60%. For carbonation, temperature was fixed at $60^{\circ}C$ and time at 1 h in the use of autoclave. Pressures were controlled to be $5kgf/cm^2$ and the supercritical condition of $80kgf/cm^2$, and gas compositions were employed as $CO_2$ 100% and $CO_2$ 15%+N2 85%. In the characteristics of produced lightweight concrete, the characteristics of lightweight foamed concrete resulting from carbonation reaction were affirmed through rate of weight change, carbonation depth test, air permeability, and processing analysis for the day 28 specimen. Based on these results, it is concluded that the present approach could provide a viable method for mass production of eco-friendly lightweight foamed concrete from CFBC coal fly ash stabilized by carbonation.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2002.11a
• /
• pp.17-22
• /
• 2002

This Waterproofing Material which mainly consisted of 2 components of waste tire chip powder and waste glass powder. This Study is abut development of waterproofing Material, There is not tried in domestic. The most Motive of this Study wishes to recycle resources and get the economic performance for waterproofing Material The result of this Study is as followings. (1) Dense waterproofing floor is formed between waste tire chip by Coupling Agent(the most effective method to encourage adhesive strength and raise cohesion of material by combination.) (2) Expected to bring effect to shorten construction period at spot application potentially space-time in moisture aspect. Also, shortening effect of construction period and spot work are considered to be gone efficiently selecting pre-mix construction method. (3) This development Waterproofing material has elasticity that nature side compatibility of cement ingredient and plastic Emulsion have when utilize and constructs waite resources (being waste tire chip and waste glass powdered).

• Journal of the Korea Institute of Building Construction
• /
• v.7 no.2 s.24
• /
• pp.77-83
• /
• 2007

This study investigated the fundamental properties of the lightweight foamed concrete depending on various admixtures, and the results were summarized as following. When 20% of cement kiln dust(CKD) and 0.002% of stabilizing agent were mixed to lightweight foamed concrete, it was necessary to use a superplasticizer because flowability was decreased. However, it could reduce sinking depth which were the extensive trouble of lightweight foamed concrete. Bulk density was divided into '0.4' and '0.5' grades on KS according to unit volume weight. The compressive strength was less than that of plain concrete when admixtures were applied, but the results exceeded the minimum strength of the each grades on KS. Totally, it is found that the combination of 20% of CKD and 0.002% of stabilizing agent makes it possible to reduce a sinking depth, recycle resources, and save cost when were mixed.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2013.05a
• /
• pp.321-322
• /
• 2013

Recently, the exhaustion of resource and environmental damage is serious due to the global warming because of the CO₂ exhaust and each type the natural aggregate picking described below. meanwhile, The rest is the actual condition gone to the dumping ground that there is nearly no use which the waste glass can recycle and it is recycled. This research applied the waste glass as the cement substitute material the inorganic binder and coares aggregate substitute material. It utilizes the substitute material of the cement according to it and natural aggregate and tries to develop the environment-friendly artificial stone. The inorganic binder used the blast furnace slag, red mud, and fly ash. The straight type steel fiber, PVA fiber, PA fiber, and cellulosic fiber were used with a kind of fiber. As to the experimental item according to it, the compressive strength is the flexural strength and compressive strength.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.24 no.6
• /
• pp.180-188
• /
• 2020

To replace Japanese coal ash used in the domestic cement production and to recycle large quantities of domestic pond ash, it is essential to develop the technologies for quality control of cement by using the domestic pond ash. Thus, in this study, the feasibility of using the pond ash as a raw material for cement was investigated through chemical composition and microstructure analysis. As a result, most of the domestic pond ash contained slightly more Fe2O3, chloride, and unburned carbon contents than Japanese coal ash. In particular, the contents of chloride were considerably low in the pond ash that was transferred to fresh water or collected from surface of landfill area. However, since circulating fluidized bed boiler coal ash had relatively high SO3 contents causing durability problems of cement, it was not suitable for use as a raw material for cement. Thus, to replace Japanese coal ash with the domestic pond ash, it is necessary to introduce the adjustment of mixture proportion of cement raw materials and the process of removing chloride in the pond ash.

• Journal of Korean Society of Environmental Engineers
• /
• v.37 no.3
• /
• pp.159-164
• /
• 2015

This study investigated the environmental risk for up-cycling of air-cooled ladle furnace slag (LFS) and evaluated the mortar compressive strength of binary and ternary blended cements using LFS of 3, 5, 10 wt%. Based on the Soil Environment Conservation Act standard, there was no environmental risk of the up-cycling of LFS. Results of mortar compressive strength assesment showed that the compressive strength of two blended cements using LFS of lower than 5 wt% was about 1.1 times superior to that of un-substituted cement (ordinary portland cement, OPC); however the compressive strength of those with LFS of 10 wt% decreased with 10% compared with that of OPC.

• Journal of the Korean GEO-environmental Society
• /
• v.4 no.4
• /
• pp.35-43
• /
• 2003

In this study, the physical and chemical characteristics of incinerated pulp and sewage sludge ashes for recycling and reuse were examined. Then we studied the application to the cement admixture by pozzolanic reaction. The particle size of incinerated pulp and sewage sludge ashes was distributed around $10{\sim}100{\mu}$, and the contents of $SiO_2$ and $Al_2O_3$ were 45.8~51.0%, respectively. Compressive strengths of the solidified ashes were relatively higher, when the content of substituted incineration ashes was 10% and the porosity was also lower except for the case of sewage sludge ash. As results, it is shown that it may be possible to recycle incinerated pulp sludge ashes as cement admixtures.