• Journal of the Korean Recycled Construction Resources Institute
• /
• v.6 no.1
• /
• pp.72-79
• /
• 2011

This study is performed to analyze the effects of CASB by applying the superplasticizer combined CASB on the ultra high strength mortar and concrete that uses different mineral admixture depending on whether the silica fume was used and the results are summarized below. From the characteristics of Fresh mortar and concrete, the fluidity was lower in B2-CASB than B2-PC from the mixing of CASB and based on the viscosity of the mortar and concrete in the binary proportion but in the ternary proportion, B3-CASB showed a larger fluidity than B3-PC because of a reduction in the restriction level due to the effects of an improvement of particle size distribution. The compression strength was higher in ternary proportion than in binary proportion and higher in CASB than in PC from the characteristics of hardening mortar and concrete and this is analyzed as a result of increased minuteness from the calcium silicate hydrates produced from the pozzolan reaction of a mineral admixture, SF, and also the charging effects of capillary pore of CASB. Overall, when using the nanomaterial, CASB in combination with a superplasticizer, the fluidity and the strength aspects of the ternary proportion of ultra high strength mortar and concrete with silica fume may be improved to a higher quality.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2011.11a
• /
• pp.55-56
• /
• 2011

This study is to investigate the engineering properties of low heat concrete incorporating improved ternary blended cement by combining OPC(original portland cement), blast furnace slag and fly ash. The results were summarized as following ; For ITB(Improved Ternary Blend)mixture was that setting time proved to be accelerated, and adiabatic temperature rises were low. The use of ITB resulted in an increase of initial compressive strength.

• Journal of the Korea Concrete Institute
• /
• v.20 no.6
• /
• pp.797-807
• /
• 2008

For this study, the semi-adiabatic temperature rising test is accomplished by using ternary system cement (OPC, BFS, FA) reducing temperature crack. Two tests are conducted; one is for the paste test, and the other is for the concrete test. As the results of paste tests, using fly ash is better to reduce hydration temperature than doing blast furnace slag. In the case of the paste mixed ternary system cement, the more fly ash is mixed and the less blast furnace slag is used, the lower the temperature is. The less the mixture ratio of blast furnace slag is and the more the mixture ratio of fly ash is, the later the temperature rising velocity and descending velocity are. Besides, the temperature is lower if water/binder ratio is high. The use of ternary system cement has the retardation effect of temperature rising because the time to reach the maximum temperature is in the order of OPC100, binary system cement, and ternary system cement. From the test, the maximum temperature of concrete used ternary system cement is $8{\sim}11^{\circ}C$ lower than that of concrete used OPC100. Moreover, temperatures rising velocity and descending velocity of ternary system cement range $47{\sim}51%$ and $37{\sim}42%$ compared with OPC100. The specimen of concrete shows remarkable low internal temperature and slow temperature rising velocity and descending velocity compared with the specimen of paste because it is that temperature loss of concrete is much more than paste specimen according to aggregates.

• Journal of the Korea Concrete Institute
• /
• v.27 no.5
• /
• pp.559-568
• /
• 2015

In this study, multi-component blended concrete mix with fly ash and ground granulated blast furnace slag according to 3 level of type of warter reduction agent (type of 0%, 8% and 16%) and 3 level of water-binder ratio (40%, 45% and 50%) was prepared for evaluation of effect of physical characteristics of concrete using multi-component blended binder according to warter reduction efficiency of warter reduction agent. In addition, concrete mix was carried out repetition test of three times in order to secure the reliability. As a result, compressive strength according to type of warter reduction agent was found that difference of strength was about 20% occurred, warter reduction efficiency of warter reduction agent was showed that a great influence on qualities of concrete. Therefore, reflected the effect of warter reduction efficiency of warter reduction agent, prediction model equations of compressive strength for multi-component blended concrete was proposed, it was found that more than 90% of the high correlation.

• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.29 no.4A
• /
• pp.347-353
• /
• 2009

The qualitative factors influencing the ingress of chloride ion into concrete are water-binder (W/B) ratio, cement type, age, chloride ion concentration of given environment, wet and dry conditions, etc. Thus, an objective of this experimental research is to investigate the effects of cement types and environmental conditions on the chloride ion diffusion characteristics in concrete through the chloride ion diffusion test. For this purpose, the diffusion coefficients for chloride ion in concrete with three types of cement such as ordinary portland cement (OPC), binary blended cement (BBC), and ternary blended cement (TBC), were measured for the concrete specimens with W/B ratios of 32%, 38%, and 43%, respectively. The diffusion coefficients for chloride ion were also measured for the concrete specimens with W/B ratio of 43%, which were subjected to standard curing and field exposure conditions. It was observed from the test results that the resistance against chloride ion penetration increased with decreasing W/B ratio and those of BBC and TBC concretes were greater than that of OPC concrete. Therefore, it was revealed that the use of these cements containing mineral admixtures is required to extend the service life of RC structures exposed to chloride environment. On the other hand, it was noted that the resistance against chloride ion penetration of field exposure test specimens was slightly lower than that of standard curing test specimens due to the penetration of chloride ion under the irregular ambient temperature, splash of wave, and cycle of wet and dry.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.05a
• /
• pp.142-143
• /
• 2014

In this study, as to enhance the efficiency and workability, binder contained 3 types of gels have been used to replacement the OPC. Fundamental properties and length change of the concrete have been tested to evaluate the effect of different binders. The following results could be made as the conclusion. When the binder contained 3 types of gels used, the flowability increased, whereas the air content decreased. There showed some different air content when the component of binder changed but the difference was consider as limit. For the strength properties, with the using of binder contained 3 types of gels increased the strength. Specimen of FA20SF5 showed the better strength and lower length change of drying shrinkage than other specimens.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.26 no.6
• /
• pp.139-147
• /
• 2022

In this study, we designed a high-strength, low-alkali type cement composite for artificial reef by mixing various binders and evaluated whether it is possible to manufacture it with an ME method 3D printer. As a result of the tests, it is found that it is important to control the water-binder ratio, the silica sand-binder ratio, and the type of silica sand in order to control the fluidity of the cement composites to enable 3D printing. The surface quality of 3D printer output can be achieved by adjusting the amount of viscosity agent added while obtaining printable fluidity. In the cement composites mixing proportion using the alpha-type hemihydrate gypsum, a setting control agent needs to be used to control the quick setting effect. It is also necessary to derive the time to maintain the fluidity, and to apply it when printing. To obtain the required strength, the mix proportion needs to be modified while satisfying the fluidity level of 3D-printable cement composites. In the present study, 3D-printable mix proportions were designed by the use of multi-component binders including alpha-type hemihydrate gypsum a for low-alkali type artificial reefs, and the printability was confirmed. A further study needs to be performed to quantitatively evaluate the alkali reduction effect.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.27 no.6
• /
• pp.111-119
• /
• 2023

Recently, a variety of new cement-based materials have been developed, and attempts to predict the properties of these new materials are increasing. In this study, we aimed to predict the rheological properties of binary blended pastes. The cementitious materials used in the study included Portland cement (PC), fly ash (FA), blast furnace slag (BS), and silica fume (SF). The three binder components, fly ash, blast furnace slag, and silica fume, were blended with cement as the foundational composition. We predicted the yield stress and plastic viscosity of the pastes using the YODEL (Yield stress mODEL) and Krieger-Dougherty's equation. The predictive model's performance was validated by comparing it with experimental results obtained using a rheometer. When the rheological properties of the binary blended paste were predicted by reconstructing the properties and parameters used to predict the individual materials, it was evident that the predictions made using the proposed method closely matched the experimental results.

• Journal of the Korea Concrete Institute
• /
• v.28 no.5
• /
• pp.593-600
• /
• 2016

The paper presented investigates the effects of kaolinite on strength properties of alkali-activated multi-component cement. The binders of this study was blended of ground granulated blast furnace slag (GGBFS), fly ash (FA), silica fume (SF) and kaolinite (KA). In this study, the specimens of combination of 20%~70% GGBFS, 10%~60% FA, 10% SF (constant ratio) and 10%~50% KA binder were used for strength properties tests. The water/binder ratio was 0.5. The binders (GGBFS + FA + SF + KA) was activated by sodium hydroxide (NaOH) and sodium silicate ($Na_2SiO_3$) was 10% by total binder weight (10% NaOH + 10% $Na_2SiO_3$). The research carried out is on the compressive strength, water absorption, ultrasonic pulse velocity (UPV) and X-ray diffraction (XRD). The compressive strength decreased as the contents of KA increase. One of the major reason for this is the low reactivity of KA compared with other raw materials used as precursors such as GGBFS or FA. The presence of remaining KA indicates that the initially used quantity has not fully reacted during hydration. Moreover, the results have indicated that increased of KA contents decreased UPV under all experimental conditions. The drying shrinkage and water absorption increased as the content of KA increase. Test result clearly showed that the strength development of multi-component blended cement were significantly dependent on the content of KA and GGBFS.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.8 no.1
• /
• pp.39-48
• /
• 2020

The present study investigates the chemical reaction and performance of ternary blended binders by mixing ferronickel slag. Cement was replaced using ground granulated blast furnace slag and ferronickel slag, combined up to 50% of the replacement rate. The blended cements were tested by setting times, length change, compressive strength at 1, 3, 7, 28 days. X-ray diffraction and scanning electron microscope were conducted for detecting hydration products while the MIP and microhydation heat were used for examining morphological characteristics. The results showed that by adding ferronickel slag, Pozzolanic reaction occurred, forming a dense pore structure and the effect of reducing hydration heat and dry shrinkage was also found. The compressive strength at 28 days was lower than that of 100% OPC control specimen (OSP0), but ternary blended cements showed no significant difference compared to binary blended (OSP50). If the optimal mix is derived later and used for the purpose, the potential for use as a cement binder is expected.