• Proceedings of the Korea Concrete Institute Conference
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• 1997.04a
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• pp.649-656
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• 1997

The properties of super-flowing concrete with low heat cement were experimentally investigated and compared with ordinary 25-240-15 concrete with type Vcement. The cement content of super-flowing concrete with the low heat cement was 400 kg/$\textrm{m}^3$. However the hydration heat of super-flowing concrete is relatively lower than that ordinary concrete with type V cement. Also the ability to resist chloride ion penetration of super-flowing concrete with low heat cement is 5 times better than that of the ordinary concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.345-351
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• 1996

The study on the properties of low-heat cement that hear of hydration is relatively lower than that of ordinary portland cement and concrete made of this low-hear cement has been performed to test the hear of hydration and compressive strength, chemical resistance of concrete using low-hear cement to compare with concrete using other several typers of cements.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.10a
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• pp.381-386
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• 1994

Recently, the design and construction of massive concrete structures are increased. But, the temperature rise within a large concrete mass make the construction of massive concrete structures be very difficult. Therefore, in Seohae Grand Bridge Project, the field measurement of hydration heat for the massive concrete footings(11$\times$22$\times$4m) was carried out. It was shown to be possible to construct the massive concrete footing successfully by application of pipe cooling system. And the measurement results showed that standard code for concrete practice was very conservative.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.789-794
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• 2002

The relationship is investigated between material modeling of concrete and the evaluation procedure of thermal stress by the hydration heat. In this respect, some important points are suggested to which special attention should be paid to reasonably evaluate the thermal stress using the widely-used structural analysis programs. This study indicates that proper material model should be used to draw incremental stress evaluation that takes into account the change of elastic modulus with time. Some correction techniques are also presented when using the program that don't have proper built-in procedure for the calculation of the thermal stress.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.13-18
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• 1998

This experiments carried out in order to investigate decreasing of the hydration heat and physical characteristics of the low blaine OPC. The experiments results indicated hydration heat was reduced by about 15% in th low blaine OPC(2300$\textrm{cm}^2$/g). The Mini-slump value of the cement paste was significantly increased and viscosity of one was decreased as blaine value in OPC decrease.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.369-374
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• 2002

In this paper, setting and hydration heat development characteristics with three binder types, type IV cement＋fly ash, type IV cement＋slag powder and type IV cement ＋ limestone powder. were investigate. As results, it was shown that the limestone powder decreased the initial setting time regardless of replacement ratio, especially the range of 20~50% replacement ratio, and the 2nd peak was shifted ahead when the limestone powder replacement ratio increased. But for the f1y ash and the limestone powder, contrary results were obtained compared with the limestone powder.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.19-24
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• 1998

In this study, blended cement with low blaine(2000, 3000$\textrm{cm}^2$/g) blast-furnace slag power by 10-70wt.% was investigated through the measurement hydration heat, physical properties. The experiment results indicated compressive strength was decreased as low blaine slag blended, but hydration heat was reduced significantly and flow of the cement paste was increased.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2005.10a
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• pp.123-127
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• 2005

EVA Powder modified high strength concretes were prepared by varying polymer/binder mass ratio with a constant water/binder mass ratio of 0.3. The effect of EVA powder on the slump, hydration heat, compressive and flexural strength, toughness and water absorption ratio was studied. In hydration heat test, temperature of hydration reaction displayed almost fixed level regardless of containing rate of EVA powder, but peak time of hydration reaction displayed late inclination as containing rate of powder increases. With the same water/binder mass ratio, the compressive strength and water absorption of EVA powder modified concretes decreased slightly when EVA powder was added and the flexural strength of EVA powder modified concretes rised slightly when EVA powder was added. Also, the toughness of the modified concretes can be improved markedly. The interpenetrating structure between the polymeric phase and cement hydrates formed at a $2{\sim}6%$(containing rate of EVA powder). The properties of the polymer modified concretes were influenced by the polymer film, cement hydrates and the combined structure between the organic and inorganic phases.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.05a
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• pp.95-100
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• 2003

The shrinkage of high strength/high performance concrete is very important property for the good working of a structure since it very often generates early age cracking due to thermal and autogenous shrinkage. Autogenous shrinkage occurs as a result of internal moisture depletion due to hydration and temperature-induced effects. The level of autogenous shrinkage occurring due to hydration also depends on temperature history at very early age. It is necessary that effect of temperature on autogenous shrinkage is investigated since the stress generated due to autogenous shrinkage is quantified. In this study, Effect of hydration heat evolution on autogenous shrinkage of high strength concretes with W/C=25-40% was investigated.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.11a
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• pp.191-192
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• 2023

This study, evaluated the effect of changes in the chemical composition of cement on the hydration reaction for carbon neutrality. For this purpose, changes in the chemical bound water and heat of hydration between current cement and past cement were compared. As a result, it was found that both the chemically bound water and heat of hydration of currently used cement decreased.