• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.643-646
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• 2005

This paper reports the influence of super retarding agent(SRA) on the setting time of concrete incorporating mineral admixture including fly ash(FA), expansive additive(EA), silica fume(SF), blast furnace slag(BS) and blast furnace slag along with fly ash(BS+FA). An increase in SRA resulted in retarding the setting time of control concrete, while the use of mineral admixture led to a delay of setting time markedly, compared with that of control concrete under no SRA content. Meanwhile, An increase in SRA in concrete with mineral admixture exhibited comparable setting delay with control concrete. Furthermore, in case of the use of BS and SF, acceleration of setting time was observed with increase of SRA content. It is considered that proper dosage of SRA of concrete with SF and BS to secure similar setting delay with control concrete require rather larger than that of control concrete. Accordingly, For concrete with mineral admixture, in order to decide the proper dosage of SRA, application of correction factors is needed.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.345-346
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• 2010

The overall quality of underwater concrete will ultimately be affected by factors such as performance of antiwashout admixture and mix proportions of concrete. Of these, performance of antiwashout admixture may significantly influence quality of underwater concrete. Thus, objectives of this experimental research are to evaluate the performance such as slump flow, setting time, compressive strength, and water segregation of the concrete containing antiwashout admixture. It was observed from the test results that concrete containing antiwashout admixture was found to improve quality of concrete such as fluidity, compressive strength, and antiwashout compared to plain concrete.

• International Journal of Highway Engineering
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• v.19 no.3
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• pp.1-10
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• 2017

PURPOSES : This paper focuses on strength development according to the mix design with cement type and mineral admixture from laboratory and field tests in cool weather. METHODS : Two methods evaluated the mix design of concrete pavement in cool weather. Firstly, laboratory tests including slump, air contents, setting time, strength, maturity, and freezing-thawing test were conducted. Three alternatives were selected based on the tests. Secondly, a field test was conducted and the optimum mix design in cool weather was suggested. RESULTS : It is an evident from the laboratory test that a mix with type III cement showed better performance than the one with type I cement. There was a delay in strength development of a mix with mineral admixture compared to mix design without any mineral admixture. In the field test, type III cement+flyash 20% mix design proved the best performance. CONCLUSIONS : For concrete pavement in cool weather, mix design using type III cement could overcome the strength delay due to mineral admixture. Moreover, it is possible to make sure of durability of pavement. Therefore, strength and durability problems due to cool weather would decrease.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.1054-1058
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• 2006

The purpose of this study was to use pig blood plasma transglutaminase (TGase) combined with thrombin and fibrinogen as a binder, which was applied to restructured meat, and to investigate its effect on the restructured meat quality. Pig meat was obtained 10 h post mortem from a traditional market was ground using a 10 mm aperture plate. A binder admixture was added (TGase:thrombin:fibrinogen mixed as 0.5:1:20 (v/v/v) to which was added 12% of its volume of 0.25 M calcium chloride) at 0, 5, 10, 15 and 20% of meat weight. Measurements included cooking loss, shrinkage rate, shear value, total plate count, pH value, TBA value, color difference, tension strength and sensory evaluation. The results showed that ground meat containing 20% w/w of binder admixture had higher cooking loss, shrinkage rate and shear value (p<0.05). Addition of different percentages of binder admixture did not affect total plate count, pH value, TBA value, and sensory evaluation of restructured meat (p>0.05). Tension strength was increased with increased level of binder admixture. Addition up to 15% binder admixture to restructured meat showed better scores of sensory texture, flavor and total acceptability (p<0.05).

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.881-884
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• 2008

Nowadays, large amount of waste pottery annually are produced. It is needed that waste pottery is to are used as recycle materials in order to prevent environmental pollution and economic profits. Therefore, the purpose of this study is to present the method of utilizing the cement admixture that is obtained from waste pottery as the cement admixture. The test results that the replacement of waste pottery powder by cement admixture at the level 5%, 7% had effect on the compressive strength of the PHC pile. As a conclusion, improved strength recycled(waste pottery powder) PHC pile can be produced of cement admixture.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.103-106
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• 2006

This study investigates spalling properties of 60MPa class, high performance concrete, made with the various influential parameters, such as, blaine of cement, mineral admixture and polypropylene(PP) fiber contents. Totally 21 parameters of ${\phi}100{\times}200mm$ in size was fabricated; three specimens for variance in blaine of cement, 4 specimens for combination of mineral admixture type, along with 0.05, 0.1, 0.15% of fiber adding ratio. After that, one hour unloading fire test was conducted, and then spalling appearance and spalling degree of specimens was examined. Test showed that a specimen made with high blaine of cement(H) improved early strength but exhibited similar value to a specimen made with low blaine(L) at the age of 28 days, thus indicating comparable spalling appearance. In conclusion, spalling easily occur in higher strength and smaller particle shape of cement and mineral admixture.

• Journal of the Regional Association of Architectural Institute of Korea
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• v.21 no.5
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• pp.117-124
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• 2019

When manufacturing concrete, several mineral admixture is added to improve the basic physical property and durability and to make economical concrete. Such mineral admixture includes fly ash, granulated blast furnace slag, silica fume, etc., and not only the studies about mixing these mineral admixtures but also the studies for the development of new materials have been steadily in progress. Recently, some researchers have found, as a part of the development of new materials, the rice straw ash can also be used as a pozzolanic material for concrete considering similar chemical properties of rice straw ash to that of rice husk ash. But there has been insufficient amount of study about it. So, this study was to investigate the possibility as mineral admixture of agriculture by-product, by analyzing properties of concretes using rice straw ash with replacement ratio in comparison with other mineral admixture. In order to measure amount of SiO2 of rice straw ash, XRF(X-ray fluorescence) analysis was tested. For the measure pozzolanic reaction of rice straw ash, pH change and color change was tested according to curing day. Also to evaluate properties of concrete using rice straw ash, slump test, air contents test and compressive strength was tested.

• Proceedings of the Korea Concrete Institute Conference
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• 2002.05a
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• pp.417-422
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• 2002

Strength and Durability of reinforced concrete exposed at deteriorated environment are decreased by cover spatting and corrosion of reinforcement. The purpose of this paper is to evaluate capacity of strengthening axial member using admixture-modified mortar. To investigate the capacity of strengthened axial member, behavior and strength of strengthening specimens were compared with a monolithic basic specimen. Admixture-modified mortar was prepared with silica fume, zeolite, polymer as cement modifier. From the result of this experiment, strengthening specimens using polymer-modified mortar have apparrent strengthening capacity because of good flexural strength and tensile strength.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.181-188
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• 2000

This study deals with the method of test for waterproof agent and admixture of cement, and especially, the effect in bond strength between waterproofing layer and mortar of concrete substrate in building construction. The purpose of this study is that it makes the estimation value of bond strength of concrete wall and anticorrosive when coated waterproof agent and admixture of cement as waterproofing materials for durability performance estimation depend on concrete watertighness.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2019.05a
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• pp.178-179
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• 2019

The purpose of this study was to investigate the possibility as mineral admixture of agriculture by-product. XRD and XRF analysis were performed on rice straw ashes at various combustion temperatures to identify chemical compositions. Also to evaluate properties of pozzolanic reaction, pH change method was tested.