• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.66-71
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• 1998

Recently, it has been increased to construct massive concrete structures, like under-ground structure, offshore structure etc., ie. concrete construction have become larger and higher and are demanding lower heat concrete to prevent thermal cracking. It has been progressed to replace cements with fly-ash and slag to lower heat of hydration, but it is hard to control quality of the mineral admixtures in stage of adjusting of real construction. Application of low heat portland(Belite Rich) cement for the mass concrete is the best solution to satisfied those requirements. Here are explained the basic properties of fresh concrete as well as hardened concrete of using low heat portland cement(LHPC). Also, we compare the results of adiabatic temperature rise test using LHPC and OPC.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.11a
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• pp.303-308
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• 2001

Recently, concrete structures have become larger and higher and are demanding high performance concrete with lower heat to prevent thermal cracking, far greater workability, high strength and durability, Application of low heat portland(Type IV) cement for the high performance concrete is the best solution to satisfied those requirements. Here are explained the effect on the properties of high flowing concrete using low heat portland cement by material and mixing variations. Variables for sensitivity test were selected items like finess modulus of aggregates, particle size of limestone powder, unit water, superplasticizer, viscosity agent and concrete temperature. The results of this study were be applied to slurry wall of #215 and #216 of underground LNG tank in Inchon.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.603-606
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• 2005

Strength development of low heat portland cement(Type IV) concrete according of addition of fly-ash in high strength range is tested. In this study strength development according to water-binder ratio, strength development according to age, effect of fly ash are tested. This study tests effect of low heat portland cement in high strength range concrete and provide guide line concrete mix design for later study and construction.

• Journal of the Korean Ceramic Society
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• v.32 no.9
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• pp.977-988
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• 1995

Several oxide (ZrO2, Al2TiO5, reactive Al2O3) and nonoxide (SiC, Si3N4, "ALON" (5AlN.9Al2O3)) additives were used as a microfiller for alumina based LCC (Low-Cement-Castable). High temperature prooperties (HMOR, softening under load) and the phase changes of developed LCC on various sintering temperatures were examined. In addition, thermal shock test and corrosion test were accomplished. Based on these data the effects of each microfiller on the properties of LCC were established comparing to those of the commercial LCC with amorphous silica as a microfiller. The castables, containing reactive alumina, ZrO2 and "ALON" (5AlN.9Al2O3) as a first portion, exhibited considerably higher HMOR-values over 100$0^{\circ}C$, better creep behavior, and thermal shock resistance than those of castables with amorphous silica. The LCC with 5% Al2TiO5 showed no corrosion against molten aluminum.nst molten aluminum.

• Journal of the Korean Ceramic Society
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• v.43 no.9 s.292
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• pp.537-543
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• 2006

Length change, hydration heat, setting time and compressive strength of OPC were measured by adding KCl and replacing limestone powder so as to examine the influence of limestone powder on hydration of the OPC contained much chloride. In general, the chloride modified cement was high in heat of hydration, short in its setting time, low in its fluidity and low in its strength at 28 days due to the sudden hydration in its initial stage. As a result of the experiment, it has been demonstrated that heat of hydration, became low as one replaced limestone powder to the chloride modified cement, and the fluidity and shrinkage rate of mortar decreased without change in setting time; furthermore, the compressive strength at 28 days was improved.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.164-165
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• 2013

This study is on the performance evaluation of concrete being used the CaMg based low carbon cement(LCC) as a binder and the rapidly cooled electric arc furnace oxidizing slag(EAF slag) as a fine aggregate. When using the sand as a fine aggregate, compressive strength of the concrete using LCC, as a binder, was reduced 9% comparing with that of OPC concrete. However, when using the EAF slag as a fine aggregate, the compressive strength was increased by 9%. We found that combination LCC and EAF slag contribute to the strength properties of concrete.

• Journal of the Korean Ceramic Society
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• v.44 no.2 s.297
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• pp.103-109
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• 2007

In this study, the rheological properties of cement pastes containing blastfurnace slag of different fineness were investigated. The fluidity of cement pastes with low Blaine value blastfurnace slag was increased with decreasing the plastic viscosity and the yield stress of pastes. And the optimum dosage of polycarboxylate type superplasticizer to the cement pastes was confirmed according to the fineness and the replacement ratio of blastfurnace slag. All cement pastes showed the thixotropy behavior. And also it was formed that the segregation range of cement pastes was occurred below $10D/cm^2$ of the yield stress and below 350 cPs of the plastic viscosity by the coaxial cylinder viscometer.

• Journal of the Korean Ceramic Society
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• v.30 no.4
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• pp.273-278
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• 1993

Using water vapor (de)sorption isotherm, pore structure analyses were performed for hardened cement pastes by a combination of the "MP-method" for the micropores and the "corrected modelless method" for the wide pores. This work was carried out to investigate the pore structure and to understand the microstructural basis of alumina cement developing much higher strength than Portland cement. Alumina cement shows extremely low microporosity and its wide pores are also composed mainlyof pores with very small radii. And the pore structure analysis results are consistent with the high strength property of alumina cement.y of alumina cement.

• Journal of the Korea Institute of Building Construction
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• v.12 no.6
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• pp.575-585
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• 2012

The extruded cement panel, which has many advantages as a prefabricated method, has been limited in its application due to its low fire-resistance. However, an extruded cement panel produced by mixing a-hemihydrate gypsum offers dramatically improved fire-resistance and is expected to have wide-ranging applications in the construction sector as an interior material or partition wall between housing units. Sound insulation performance is very important for the partition wall between housing units. In this study, the sound insulation performance of the extruded cement panel produced through the mixture of a-hemihydrate gypsum is reviewed in order to determine its usability for a partition wall between housing units and for interior materials. Through the review it was found that the wall formed using the extruded cement panels produced by mixing the a-hemihydrate gypsum have ★★★ class in sound insulation test, equal or superior compared with the other two types of extruded cement panel walls currently available in the market.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.47-52
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• 2000

Recently, it is very necessary the development of the manufacturing techniques for high strength concrete(HSC) for the large-scale size and good quality of civil structure. But, the manufacture and quality control of HSC of which shrinkage, heat of hydration and workability at construction filed are considered, is very difficult due to its low water-cement ratio and high quantity of unit cement content. In the present study, we tried to know and assess the influences of chemical and physical properties of cement on the material properties of HSC. We analyzed basic properties of 4 kinds of cement whose chemical and physical properties are different each other through various tests such as chemical analysis and mortal test. Also, we performed the assessment of the material properties of HSC for each dement by the test for the conditions of same mix design and similar compressive strength. From the results in the study, the assessment of the important quality factors of cement influencing the properties of HSC may be utilized to quality control of applied cement to manufacture the HSC of high quality.