• Journal of the Korean Ceramic Society
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• v.42 no.3 s.274
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• pp.182-187
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• 2005

There are many kinds of polycarboxylate superplasticizer as a functional classification which are introduced to domestic; Water Reducer, Retention, Ultra High Strength Superplasicizer. These are showed different physical behaviors because of the difference in the chemical system and the manners after cement mixing. In the case of water reducer, when $1.2\% of cement weight used, water reducing which is over $30\% is observed, but it take with segregation and the reduction of slump flow shows over 30 cm after 45 min of concrete produce. In the case of retention, when the same quantity used, water reducing which is about $25\% is observed and slump flow which is up to 45 min shows under 15 cm. And in the case of ultra high strength, when $1.2\% of cement weight used, water reducing which is over $30\% is observed, and slump flow which is up to 45 min recorded fewer than 15 cm. Compressive strength of ultra high strength superplasticizer has take effect of early age strength, and in the condition of specific mixing, 18 h-compressive strength is insured for more than $60\;Kgf/cm^2$ and 24 h-compressive strength is insured for more than $80\;Kgf/cm^2$.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.3
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• pp.62-69
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• 2012

This study investigates the engineering properties of the high strength concrete depending on dosages and types of shrinkage reduction agent. Test results showed that for the properties of fresh concrete, the addition of the conventional shrinkage reduction agent (SR) of 0.25% decreased slump flow up to 40% as compared with control concrete, whereas the addition of the emulsified waste cooking oil (EWCO) decreased slump flow of only 5% to 10%. Other properties of fresh concrete with the agents, namely air content, unit weight and setting time, were similar to the results of the control concrete. For the properties of hardened concrete, the compressive strength of the concrete with SR decreased at both early and later stage. However, the compressive strength of the concrete with EWCO was similar to the control concrete at early age, but decreased at later stage (up to 10% reduction at 28 days). For the effect of the agents on autogenous shrinkage of the concretes, the addition of EWCO decreased up to 33%, whereas that of SR decreased up to 29%. Hence, it can be said that the addition of EWCO in high strength concrete has an effect on reducing the autogenous shrinkage as compared with a conventional agent and only slight influence on the slump flow and air content of concrete. By taking all aspects of using EWCO, it is concluded that the optimum content of EWCO will be in the range of between 0.5% and 0.75%.

• Proceedings of the Korea Concrete Institute Conference
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• 1994.10a
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• pp.121-126
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• 1994

In this study, several rheological properties of binder pastes and concrete are investigated for the development of commercially available fly ash super-flowing concrete. Fly ash contents with 5 leves(0, 10, 20, 30, 40%), slag contents with 6 levels(0, 5, 15, 25, 35, 45%), and water-binder ratios with 4 levels(30, 33, 36, 39%) are selected for test variables to evaluate the super-flowing characteristics of binder pastes. For the estimation of the workability of super-flowing concrete, slump flow, funnel time, box height, and L-flow are measured and compared. As the results, the flow is decreased and the viscosity is increased with increasing fly ash content. Super-flowing concrete is succesfully produced with 30% fly ash replacement.

• Proceedings of the Korea Concrete Institute Conference
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• 2005.11a
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• pp.675-678
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• 2005

Cement paste is originally the basic material and crucial factor consisting concrete. This study investigates the relationship between flow apparatuses, which are ring flow, flow cone and mini slump, in order to estimate the fluidity of cement paste. For quantitatively evaluating the measured data, this study also analyses the calibration of the rheology consistents of cement paste using viscometer. For this purpose, the present work discusses the influence of the differences of companies and ingredients, affecting the fluidity of cement paste

• International Journal of Concrete Structures and Materials
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• v.6 no.1
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• pp.59-64
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• 2012

Sand-concrete is being researched for potential usage in construction in Saharan regions of Algeria, because of shortage in coarse aggregate resources. This research work deals with the effect of dune sand, available in huge quantities in these regions, on the properties of flowing sand-concrete (FSC) prepared with different proportions of dune and river sands. Mini-cone slump test, v-funnel flow-time test and viscosity measurements were used to characterize the behaviour of FSC in fresh state. The 28-day compressive strength was also determined. Test results show that an optimal content of dune sand, which makes satisfied fresh and hardened properties of FSC, is obtained. Moreover, the obtained flow index (constant b) calculated by the help of power-law viscosity model is successfully correlated to the experimental results of v-funnel flow time.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.10a
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• pp.95-98
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• 1999

Recently, the use of the underwater concrete constructions with the antiwashout underwater concrete is increasing. In this study, we investigate the properties of pH, suspended solids, slump flow, box test, air contents of fresh antiwashout underwater concrete and the Unit weight, compressive strength of hardened antiwashout underwater concrete which Ground Granulated Blast Furnace Slag contents 0%, 10%, 20%, 30%, 50%, 60% at 7days and 28days age which is produced and cured in the water and sea water. As a result, Ground Granulated Blast Furnace Slag contents 30% was excellent.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.10c
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• pp.83-86
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• 1998

Recently, underwater concrete constructions are increasing. Therefore it is considered important to control the quality of underwater concrete. In this paper, we have an intention of evaluating fundamental properties of underwater concrete using the Ground Granulated Blast Furnace Slag (GGBF Slag). Thus, it has been investigated that the slump flow of the concrete, pH value and suspended solids in solution, compressive strength on both of specimens made above and below water. Also the percentage of GGBF Slag was found to alter the filling-up in underwater concrete.

• Proceedings of the Korea Concrete Institute Conference
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• 1991.04a
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• pp.87-92
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• 1991

Since the material property of binder in polyester polymer concrete has a viscous mechanism, the workability of polyester polymer concrete mixture showed different characteristics from that of cement concretes. Therefore, this study was devised to evaluate workability characteristics of polyester polymer concrete using slump and flow tests. Study results showed that the test temperature and ST/UP ratio were the most dominantly affecting factor on the viscosity of binder, and viscosity of the binder was strongly correlated with the workability of polyester polymer concrete mixture.

• Proceedings of the Korea Concrete Institute Conference
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• 2003.11a
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• pp.457-460
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• 2003

This paper discusses laboratory evaluations to assess the physical properties of antiwashout underwater concrete (AWC) containing pozzolanic materials such as fly ash (FA), blast furnace slag (SG) and metakaolin(MK). For the experiments, pH value, suspended solids, slump flow, efflux time and compressive strength were tested. According to the results from compressive strength test, MK10 showed the very high compressive strength characteristic during the entire curing days, but the rate of strength development was decreased as time goes by.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.267-270
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• 1998

Recently, underwater concrete constructions are increasing. Therefore it is considered important to control the quality of underwater concrete. In this paper, we have an intention of evaluating fundamental properties of underwater concrete using the anti-washout admixtures. Thus, it has been investigated that the setting slump flow of the concrete, pH value and suspended solids in solution, compressive strength on both of specimens made above and under water. Also the percentage of fine aggregate has been found to alter the compressive strength in underwater concrete.