• Resources Recycling
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• v.8 no.4
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• pp.30-38
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• 1999

High 1emperiltur.e propeitles o i cold bonded pellet based on lroll beanng dusts wele invesligaled prim to using as a burden m blasl furnaces, Major conclusions ould be summarized Io llows: the cold bonded pellet needed to bc produced by the characteristic criterion on high lempemhIre prapcrttes as well as a compressive sncnglh. Basicity of cold bonded pellel shruld be linted to be appoxiiniltely 1.7 in order to maintain appropriate softcn~nga nd rnelt~ngp ropcrlies. On thc other hand. basiciq greater than 2.6 showed exce\ulcornersive puessure drop due to powder gelleratlon. Potcntialil], of blast fi~rnaccs lag as binding malerial in m a h g cold ba~~deprel llels !\.us also certified in viewpoinls of high temperature properly.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.375-376
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• 2009

This study aims to provide basic material of concrete in replacement of non firing Hwang-toh, a traditional construction material in order to reduce CO$_2$ produced during manufacturing due to effectuation of the current Kyoto Protocol.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.5
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• pp.119-126
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• 2018

Recently, the production of circulating fluidized bed combustion ash has been increased in thermal power plants. The addition of limestone for the desulfurizing effect of circulating fluidized bed boiler ash increases the content of CaO and $SO_3$ contained in ash, which is higher than the free fly ash in general fly ash. Unlike conventional fly ash, the circulating fluidized bed combustion ash has a high reactivity when it comes into contact with water due to its hydraulic properties and high free-CaO content. The aim of this study is to investigate the possibility of non-sintered binder by using self-cementing properties of circulating fluidized bed combustion ash. The mechanical and hydration characteristics were investigated according to the content of CFBC ash. In addition, the effects of gymsum type and content on the compressive strength and micro-structure of non-sintered binder pastes.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.34-35
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• 2021

In this study, we compared and analyzed hydration heat of the Concrete(NC) and non-fired Hwangto Concrete(HT). The Concrete(NC) was based on the mix that showed 30, 45 MPa on compressive strength on 28th and Only cement was used to make it. and We substituted 30% of weight of unit cement to non-fired Hwangto to create non-fired Hwangto Concrete(HT).

• Journal of the Korea Institute of Building Construction
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• v.18 no.2
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• pp.109-115
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• 2018

Since the current method of SCW cement milk pouring method uses one to one ratio of cement milk with OPC, there are some problems such as drying shrinkage, increased cost, difficulty of controlling mix proportions for various conditions of applied soil, and precipitation of $Cr^{6+}$ due to the excessively used cement. Specifically, in aspect of sustainability issues of cement manufacturing, the consumption of cement should be reduced. Hence, in this research, as a replacement of cement for SCW method, blast furnace slag with sulfate or alkali as a stimulant, and expansive admixture were used. By using blast furnace slag as a hardening composite of SCW, there are many advantages such as free controllable mix proportions, rapid setting time with less mud occurrence, less cost with less energy for mixing, constant strength development, and less precipitation of $Cr^{6+}$. Regarding the alternative composites for SCW, in this research, durability and chloride resistance were evaluated.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.609-612
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• 2006

The quality of the concrete compression strength can be determined after the passage of 28 days, but if any defect is found the quality of concrete after that length of time, there can be serious problems in dismantling and repair. Thus, in response to the use of concrete using non sintering cement (NSC), the present study purposed to propose a method of managing the strength of high strength concrete using NSC in comparison with high strength concrete using ordinary Portland cement (OPC) through early strength estimation using microwave, which enables the quick estimation of the strength of high strength concrete using NSC.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.05b
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• pp.357-360
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• 2005

This research investigates the drying shrinkage of non-sintering cement(NSC) matrix added phosphogypsum(PG) and waste lime(WL) to granulated blast furnace slag(GBFS) as sulfate and alkali activators with various curing condition. The experimental results are follow: When the moisture is fully supplied at the early curing age, there is effect which carries out abundant generation of the ettringite which is an expansion nature mineral, and compensates for contraction with a chemical prestress concept.

• Journal of the Society of Disaster Information
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• v.11 no.3
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• pp.329-336
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• 2015

When diatomite powder was used as an admixture in mortar, its effects on the mortar strength was examined by experimental tests. For the tests, 4 kinds of commercially available diatomite powder were purchased ; one non-calcined product, one calcined product, and flux-calcined product two. The compressive and flexural strength of the mortar according to the increase of added amount of calcined diatomite powder increased at all test ages(7, 28, and 56 days). However, the use of non-calcined diatomite powder worsened the fluidity of mortar severely and that caused much more required water content. And flux-calcined product did not show useful effect on the mortar strength.

• Journal of the Korea Institute of Building Construction
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• v.15 no.4
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• pp.359-365
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• 2015

Floor mortar experiences dry shrinkage by temperature and humidity difference of internal matrix with material type. Also, since floor mortar is influenced by environmental conditions during placing and curing period, cracks are likely to be occurred. In this study, it was evaluated the hardening and dry shrinkage properties of non-sintered binder based floor mortar utilizing alpha-hemihydrate gypsum which has expansibility in order to prevent crack of the floor mortar. It was applied to the construction site, and examined the effects of external environmental conditions on shrinkage deformation and cracking. Different types of slag accelerated initial and final setting in comparison with cement mortar and its compressive strength was satisfied standard compressive strength for floor mortar. Also shrinkage deformation behavior after the initial expansion exhibited a similar tendency with the cement mortar. From the field application result, no crack was found from slag mortar, and it is determined that the slag mortar has better dimensional stability than cement mortar caused by external environment conditions.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.05b
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• pp.453-456
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• 2006

If cement can be manufactured with industrial byproducts such as granulated blast furnace slag(GBFS), phosphogypsum(PG), and waste lime(WL) instead of clinker as its counterproposal, there would be many advantages, including maximum use of these industrial byproducts for high value-added resources, conservation of natural resources and energy by omitting the use of clinker, minimized environmental pollution problems caused by CO2 discharge, and reduction of the production cost. This research investigates the chloride ion permeability of NSC concrete added PG and WL to GBFS as sulfate and alkali activators. The result of experiment of chloride ion permeability, showed that NSC is very excellent in seawater resistance. Such a reasons are that the hydrate like CSH gel and ettringite formed dense pore structure of NSC matrix.