• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.51-52
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• 2013

Generally, Adiabatic temperature rise and temperature rise rate are reported to increases when placement temperature, W/B and the unit water content is fixed. In this study, properties of adiabatic temperature rise on placement temperature consider the hot weather environments from of W/B 0.29, 0.34, 0.40 was reviewed, the amount of cement on mixing condition of the same W/B and unit water content evaluated on the impact of the adiabatic temperature rise. As a results, the adiabatic temperature rise of concrete is proportionate to binder as well as the cement content under the same unit water content.

• Computers and Concrete
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• v.17 no.2
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• pp.271-280
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• 2016

This study examined the mechanical properties and adiabatic temperature rise of low-heat concrete developed based on ternary blended cement using ASTM type IV (LHC) cement, ground fly ash (GFA) and limestone powder (LSP). To enhance reactivity of fly ash, especially at an early age, the grassy membrane was scratched through the additional vibrator milling process. The targeted 28-day strength of concrete was selected to be 42 MPa for application to high-strength mass concrete including nuclear plant structures. The concrete mixes prepared were cured under the isothermal conditions of $5^{\circ}C$, $20^{\circ}C$, and $40^{\circ}C$. Most concrete specimens gained a relatively high strength exceeding 10 MPa at an early age, achieving the targeted 28-day strength. All concrete specimens had higher moduli of elasticity and rupture than the predictions using ACI 318-11 equations, regardless of the curing temperature. The peak temperature rise and the ascending rate of the adiabatic temperature curve measured from the prepared concrete mixes were lower by 12% and 32%, respectively, in average than those of the control specimen made using 80% ordinary Portland cement and 20% conventional fly ash.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.155-160
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• 1998

In this study, the estimation method of adiabatic temperature rise of concrete was developed by using hydration heat generation of mineral compounds of clinker and pozzolans. Specific heat considered the effects of mix proportion and temperature was calculated with experimental data. The adiabatic temperature rise calculated by developed method were compared with experiments in which many types of cement and admixtures were used. As the results of this study, it was found that the developed method could calculate adiabatic temperature rise of concrete accurately without the experiment.

• Advances in concrete construction
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• v.12 no.5
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• pp.439-450
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• 2021

In recent years, nano-reinforcing materials are widely utilized in cement composites due to their unique multifunctional properties. This study incorporated multi-walled carbon nanotubes (MWCNTs) into the cementitious composites at ratios of 0.1%, 0.3%, and 0.5%, and investigated their influence on the flowability, mechanical strength, and hydration heat properties. The addition of MWCNTs enhanced the compressive and split tensile strengths approximately by 18-51%. In the semi-adiabatic temperature rise test, the internal hydration heat of the composites reduced by 5%, 9%, and 12% with the increase of MWCNTs in 0.1%, 0.3%, and 0.5%. This study further performed hydration heat analysis and estimated the adiabatic temperature rise, thermal stress, and thermal crack index. The internal hydration heat of the concrete decreased by 5%, 10%, and 13% with the increase of MWCNTs. The thermal stress of the concrete decreased with increase in the addition of MWCNTs, and the obtained temperature crack index was effective in controlling the thermal cracks.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.527-532
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• 2001

The crack of concrete induced by a temperature rise in early age concrete due to the heat of ration of cement is a serious problem for massive or high strength concrete structures. However, re is still no reasonable equations for the prediction of the temperature rising. On this study, the prediction equations of the heat of hydration of different types of binder are pained from the adiabatic temperature rise test, and compared with the results from different nations to obtain the best approximated equation. The strengths of concrete of which specimens were placed in the same chamber for the adiabatic to were compared with those under standard curing.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.309-310
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• 2010

In this study we investigated the properties of the fundamental and adiabatic temperature rise of the concrete using high volume fly-ash. For this, the fly ash was used to replace cement at replacement ratio of 40% and 50% by mass, and then the slump, air content, bleeding, compressive strength and adiabatic temperature rise test of concrete were performed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.56-57
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• 2013

In this study, in regard to concrete considering variety of admixture content rate, we evaluated property of adiabatic temperature rise. By setting up high temperature history, we evaluated effect to compression strength property of high strength concrete by early high temperature history. As a result, early high temperature history accelerated Hydration reaction of cement and contribute early strength development but it didn't accomplish performance objective in long-term aged.

• Journal of the Korea Institute of Building Construction
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• v.21 no.6
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• pp.563-571
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• 2021

Recently, due to the increase in high-rise apartment and residential-commercial complex buildings, a number of mega-class mass concrete members with a thickness of 3m or more have been designed. As the construction of mass concrete such as transfer beam and slab is increasing not only in foundation members but also in special structures, research on reducing temperature cracks in mass concrete is being conducted. To review temperature cracks in mass concrete, it is important to review the thermal properties of concrete, but it is difficult to use an adiabatic temperature rise tester in the field, so the semi-adiabatic temperature rise test is mainly used. In this study, to improve the accuracy of the results of concrete heat characteristics gained by the semi-adiabatic temperature rise test, various factors affecting heat loss compensation and methods were reviewed and presented.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2007.11a
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• pp.45-48
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• 2007

This study investigates mechanical properties of the concrete using coarse particle cement which is manufactured by the classifying process. The variable factors are 3 types of W/C such as 40, 50, and 60% and 5types of the replacement of the coarse particle cement such as 0, 25, 50, 75, and 100%. As the results, amount of SP agent to secure the target fluidity is gradually declined in accordance with increasing CC replacement. There is no special tendency for target air content, but setting time is delayed according to increasing CC content. The peak of the simple adiabatic temperature rise is gradually decreased in accordance with increasing CC content, and approach time to peak is slightly delayed. The compressive strength is comparatively delayed.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.114-115
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• 2021

The research team conducted a series of studies to use CGS as fine aggregate for concrete. In this paper, through the adiabatic temperature rising test, CGS' hydration heating performance and its usability as a mass concrete hydration heating agent were reviewed. According to the analysis, the maximum temperature of the mix of OPC 100 was 53.7℃, and the temperature of CGS 50% was 45.2℃, which was 8.5℃ lower than the OPC 100.