• Journal of the Korean Ceramic Society
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• v.37 no.5
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• pp.453-458
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• 2000

Glasses showing the composition of blast furnace slag were made in the laboratory, and the effect of the chemical composition on the latent hydraulic activity of the slags was examined. The latent hydraulicity was greatly influenced by the composition change, the optimal characteristic of the hydraulicity was achieved at the slag composition of 47CaO:20Al2O3:33SiO2. The content of CaO and Al2O3 were not equivalent to the hydraulic activity of the slags as the b-formula (KS L 5210) indicates. Good latent hydraulicity was shown when Al2O3 was richly contained at the high (CaO＋Al2O3):SiO ratio, while the more the MgO content was, the more negative the result turned out.

• Journal of the Korean Ceramic Society
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• v.34 no.5
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• pp.491-499
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• 1997

High flexible lightweight composites containing tobermorite as a main mineral is produced using various amorphous silicates, lime, cement and fibers. Here, Mechanical properties of the composites were studied by observing microstructures of hydrates and fibers. Amorphous silicates having better hydraulicity retarded the crystallization of tobermorite due to better formation of C-S-H gel in water bath curing, but, difficult conversion from C-S-H gel to tobermorite in hydrothermal reaction. In the low molar ratio of CaO/SiO2 (0.67), faster crystalization was observed dued to more impurities such as Al2O3 alkali, resulting in improving mechanical properties due to small crystal size and many contact points. It was identified that a lot of calcium silicate hydates formed at surface of pulps increase bonding strength and the crack-resistance of matrix in the composites, but decrease hardness and compressive strength. The choice of amorpous silicates having better hydraulicity, low CaO/SiO2 adding each fibers bellow about 5% in the raw mixs and lower molding pressure should be needed at improve mechanical properties of composites.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.05a
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• pp.99-102
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• 2008

This study investigates the properties of the flow, air content, strength, hydration heat, and the autogenous shrinkage, and the results are summarized as following. As a properties of fresh concrete, the flow increased and the air content decreased as the replacement ratio of BS increased. The time of set delayed as the replacement ratio of BS increased by latent hydraulicity. The compressive strength of hardening concrete was smaller than OPC as the replacement ratio of BS increased at young concrete, however it was more than equal after 28th day and from then on. The rising temperature ratio which occurs by simplicity insulation decreased as the replacement ratio of BS increased, but it increased by latent hydraulicity reaction at the latter half. The length ratio of autogenous shrinkage of OPC was 319×10^-6, however it was shorter when the replacement ratio was 40% as showing 290×10^-6.

• The Korean Journal of Ceramics
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• v.2 no.3
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• pp.147-151
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• 1996

By adding borax into the raw mix, Modified Belite Cement clinker and cements were prepared. Clinkerization and hydration reactions were investigated in order to better understand. Borax-bearing MBC clinker sintered at 1300℃ for 1 hour showed excellent burnability. Borax stabilized α'and β-C2S at room temperature. In the hydration of the cement prepared with the borax-bearing clinker, ettringite, monosulphate, C-S-H hydrates and CH were formed. The hydration of calcium sulphoaluminate was less reactive than the cement prepared with the controlled clinker at early hydration time. But, as hydration time elapsed, this cement showed more active hydraulicity and higher compressive strength development.

• Proceedings of the Korea Concrete Institute Conference
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• 1995.04a
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• pp.72-77
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• 1995

Blast-furnace slag cement has been used widely as a structural material due to the latent hydraulicity of granulated ground blast furnace slag(GGBS)for a long time as The wall as ordinary portland cement. In this study, based on the fundamental investigation on the high strength and high durable concrete using the high fineness GGBS the following remarks can be made. 1) The average desired strenth of concrete is Or=600~800kg/$\textrm{cm}^2$. 2) The above high strength concrete using the high fineness GGBS is more workable than those using only OPC. 3) The adiabatic temperature and drying shringkage decrease, so the density and resistance to sea water attack increase as results. 4)The unit cement content and unit air entrained admixture at the same desired strength of concrete decrease, so the economical high strength concrete can be manufactured from using the high fineness GGBS.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.307-308
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• 2009

The ultra high strength concrete classed 80 MPa for Lotte Town at pusan has many hydrated materials due to low water to binder ratio and high admixture contents and improved void structure caused by C-S-H gel corresponding to pozzolan and latent hydraulicity of FA and BS. Moreover, durability of the concrete is superior because there was no penetration of carbon dioxide, chloride and chloric ion caused by its fine internal constitution.

• Journal of the Korean Ceramic Society
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• v.27 no.3
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• pp.437-443
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• 1990

The resistivity of cement paste and mortar for freezing and thawing was investigated for densifying the structure of cement paste and mortor, slag, diatomaceous earth and fly ash as blending materials and superplasticizer were used, and air entraining agent was added to absorb the volume expansion by freezing and thawing reaction. And then the specimens were subjected to freeze-thaw in water. When both of air entraining agent and superplasticizer as additives were mixed to specimens, their freeze-thaw resistance was enhanced by the air entraining effect and the water reduction effect. When 4% of slag were added to cement, freeze-thaw resistance was especially excellent. In addition, it was found that the specimens with blending materials were more influenced by curing periods than those without admixture. It is assumed that the curing periods contribute to exibit the potential hydraulicity and pozzolanic reactivity of blending materials and to densify their texture.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.11a
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• pp.251-252
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• 2011

This study is to investigate experimentally the strength properties of mortar using recycled fine aggregates(RA) and blast furnace slag powder(BS) without cement according to type of fine aggregate. In the results of the study, compressive strength of RA was the highest. It can be considered that the results are due to the reaction of the non-hydration cement in RA to the latent hydraulicity reaction of the BS.

• KIEAE Journal
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• v.6 no.2
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• pp.11-18
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• 2006

In this research, Conducting an engineering properties experiment, this study examined basic properties of regional Hwangto. The results of experiments are as followings. 1) This study confirmed that a result of examining lime order for Hwangto and comparison of stimulants, this study confirmed that 28 day's strength promotion is found in case of calcium hydroxide(Ca(OH)2) and calcium chloride(CaCl2) stimulant. Finally, it is known the fact that lime highly improves the weak strength of Hwangtoh. 2) As XRD analysis for proving the strength manifestation principle of Hwangto by regions, CSH figure and CASH figure appeared in each regional Hwangto in all the strength areas. This result could be appeared through hydraulicity from reaction of alkali stimulant and water, and pozzolan reaction(CSH figure) and $Str{\ddot{a}}tlingite$ reaction(CASH figure) by silica (SiO2) ingredient and calcium hydroxide (Ca(OH)2) among ingredients of clay, and alumina(Al2O3). 3) In result of strength analysis, It is knowned that the Gyeongsangdo Hwangto is stronger than the Jeollado Hwangto in reactivity.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.2
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• pp.107-113
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• 2013

This study is the study desiring to solve the problem by utilizing the kinds of recycled resources considered to be troubled complementarily. Namely the reaction of potential hydraulicity of Blast Furnace Slag Powder (BS) shall be reacted with the alkali of Recycled Fine Aggregates Coarse Aggregate, it has been experimented to obtain the optimum value with the replacement ratio of incineration plant ash (WA) treated with the slaked lime as the experiment variable by solving the alkali of shortage with the Ordinary Portland Cement (OPC). As a result, the liquidity and the air volume are declined slightly as the replacement ratio of incineration plant ash WA increases, the mixture of incineration plant ash WA 1% has been analyzed to be the most suitable considering the viewpoint of effective handling of waste as the compression and the tensile strength showed the maximum value before and after 1% even though it was disadvantageous with the increase of chloride content.