• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.05a
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• pp.72-73
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• 2021

For the development of high-fluidity concrete using low-binder, The effect of the use of the developed acrylic viscosity agent on the physical properties of concrete evaluated. The amount acrylic viscosity agent used was 1.5%, 1.7%, and 2.0% based on the binder amount of 400kg/m3, and slump flow test, slump flow 500mm arrival time measurement, air volume measurement, and U-Box passing test were conducted to determine the effect of the physical properties of concrete. it was judged that 1.5% of the acrylic viscosity agent used in high-fluidity concrete using low-binder was most suitable.

• Journal of the Korea Concrete Institute
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• v.18 no.5 s.95
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• pp.649-656
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• 2006

In this study, powered superplasticizer(PSP) agents to improve the slump loss rate of recycled aggregate concrete were developed. To evaluate the variation of fluidity against elapsed time and the mechanical properties, twenty four specimens whose main variables had the mixing condition of aggregates, such as natural and recycled gravels, and natural and recycled fine aggregates, were tested. The concrete slump with a liquid superplasticizer greatly decreased against the elapsed time and dropped by less than 50% of initial slump after two hours. However the concrete slump with the PSP agents hardly varied until after half an hour and maintained more than 85% of initial slump even after an hour. Also the PSP agents made the compressive, splitting tensile, and flexural strength of concrete increased and the shrinkage strain decreased. Considering the properties improvement of concrete, it can be recommended that optimum mixing amount of the PSP agents should be 5% of the amount of cement.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05b
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• pp.67-68
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• 2010

Recently, there were not enough studies regarding the mix adjustment and changes of normal physical properties of slump flow type concrete in domestically. Therefore in this paper, it is aimed securing the fundamental data about flow its mix design method by experimental research. The experiment includes the adjustment of the way for slump flow type concrete by the variation of size of coarse aggregate. In the result, it is advisable raising the ratio of fine aggregate and unit water amount by considering the specific surface when increasing the Gmax size.

• Journal of the Korean Society of Industry Convergence
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• v.5 no.2
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• pp.103-110
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• 2002

An artificial neural network is applied to the prediction of compressive strength, slump value of concrete. Standard mixed tables arc trained and estimated, and the results are compared with those of experiments. To consider the varieties of material properties, the standard mixed tables of two companies of Ready Mixed Concrete are used. And they are trained with the neural network. In this paper, standard back propagation network is used. For the arrangement on the approval of prediction of compressive strength and slump value, the standard compressive strength of 210, $240kgf/cm^2$ and target slump value of 12, 15cm are used because the amount of production of that range arc the most at ordinary companies. In results, in the prediction of compressive strength and slump value, the predicted values are converged well to those of standard mixed tables at the target error of 0.10, 0.05, 0.001 regardless of two companies.

• Journal of the Korean Ceramic Society
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• v.37 no.2
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• pp.145-151
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• 2000

In order to investigate the rheological properties of belite-rich cement(BRC) added polycarbonate-based superplasticizer and blastfurnace slags which have different blaines at 4500, 6000 and 8000$\textrm{cm}^2$/g, the change of minislumps and mortar slumps are measured with time. The rheological properties improve as specific surface area of added slag decreases or amount of polycarbonate-based superplasticizer increases. The slump loss can be controlled effectively by the steric hinderance effect of polycarbonate-based superplasticizer. According to the results, when mix proportion of the mortar is 1.5% mass content of superplasticizer and 30% mass addition of blastfurnace slag which blaine is 4500$\textrm{cm}^2$/g, the best mortar slump can be achieved without any significant segregation of materials.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2021.11a
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• pp.129-130
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• 2021

For the development of high-fluidity concrete using low-binder, The effect of the use of the developed acrylic viscosity agent on the physical properties of concrete evaluated. The amount acrylic viscosity agent used was 0.28%, 0.29% and 0.30% based on the binder amount of 350kg/m³, and slump flow test, air volume measurement, U-Box passing test and strength compressive were conducted to determine the effect of the physical properties of concrete. it was judged that 0.29% of the cellulose type viscosity agent used in high-fluidity concrete using low-binder was most suitable.

• Proceedings of the Korea Concrete Institute Conference
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• 1996.10a
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• pp.290-294
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• 1996

High-Belite cement had a better slump flow characteristics than type I cement and slag cement, and its varation of slump flow with time was also excellent. As the amount binder added was increased, the strength increased while material separation decreased. This phenomena was obvious when the amount of cement was abobe 500kg/$\textrm{m}^3$ . When the amount of cement and S/a were 516kg/$\textrm{m}^3$ and 52% respectively, the application strength of 600kg/$\textrm{m}^3$ was satisfied. Since, however, the aggreate size of 25mm was somewhat unsatisfactory, the characteristics of high performance concrete could be obtained by the addition of the viscosity-enhancing agent.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2008.11a
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• pp.89-92
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• 2008

This research analyzed the basic characteristics of unhardened concrete and the compression strength characteristics of hardened concrete according to liquidity retention agent mix rate change to improve the liquidity fluidity retention performance of high performance concrete, and produced the following results. The moment fluidity retention agent is added according to fluidity retention agent mix rate change, which increased fluidity retention agent mix rate, slump flow decreased, and in the case of slump flow according to the progress time change by the fluidity retention agent mix rates, the more fluidity retention agent mix rate increased, the lower slump flow change rate became. The moment fluidity retention agent is added according to fluidity retention agent mix rate change, fluidity retention agent mix rate increased compared to non-mixture of fluidity retention agent, and the air amount by progress time change by the fluidity retention agent mix rates slightly increased, however target range is still met and unit volume mass is inversely proportional to air amount. Compression strength according to age progress by the fluidity retention agent mix rates was shown to increase slightly with increase in fluidity retention agent mix rate, and yet the difference was not significant.

• Journal of Ocean Engineering and Technology
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• v.12 no.1
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• pp.153-161
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• 1998

This paper is to investigate the Fluidity of Antiwashout Underwater Concrete containing Fly Ash. The results of study are concluded as follows: the increase in Slump Flow value did not happen in the plain concrete which was replaced cement by Fly Ash; however, the maximum value could reach in the replacement of 30% of Fly Ash by weight of cement in the Fly Ash replaced concrete. On the condition of Fly Ash-Antiwashout Underwater Concrete in expecting 50 cm of the Slump Flow, it was necessary that the usage amount of Superplasticizer be around 1% of unit Binder, and 1.5% in 60 cm of the Slump Flow, respoectively.

• Proceedings of the Korea Concrete Institute Conference
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• 2001.05a
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• pp.25-30
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• 2001

The purpose of this study is to present a basic data about the workability of high strength concrete to apply to a field of construction work. The main parameters are as follows; environmental temperature, elapsed time and the use of mineral admixture or not under the same mixing proportions. From the result, Adding amounts of superplasticizer to get a target slump were different in the respective temperature condition. Slump loss according to elapsed time was influenced by environmental temperature. the amount of superplasticizer and the slump loss were decreased by using mineral admixture(garnet powder) and by making concrete under lower temperature.