• Journal of the Korea Concrete Institute
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• v.25 no.4
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• pp.457-465
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• 2013

This study discussed the influence of mixtures and curing conditions on the development of strength and microstructure of RPC using ternary pozzolanic materials. Through pilot experiment, various RPC was manufactured by adding single or mixed ternary pozzolanic materials such as silica fume, blast furnace slag and fly ash by mass of cement, up to 0~65%, and cured by using 4 types of method which are water and air-dried curing at $20^{\circ}C$, steam and hot-water curing at $90^{\circ}C$. The results show that the use of ternary pozzolanic materials and a suitable curing method are an effective method for improving development of strength and microstructure of RPC. The unit volume of cement was greatly reduced in RPC with ternary pozzolanic materials and unlike hydration reaction in cement, the pozzolanic reaction noticeably contributes to a reduction in hydration heat and dry shrinkage. A considerable improvement was found in the flexural strength of RPC using ternary pozzolanic materials, and then the utilization of a structural member subjected to bending was expected. The X-ray diffractometer (XRD) analysis and Scanning Electronic Microscope (SEM) revealed that the microstructure of RPC was denser by using the ternary pozzolanic materials than the original RPC containing silica fume only.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.68-71
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• 2013

Reactive Powder Concrete (RPC) is an ultra high strength and high ductility cement-based composite material and has shown some promise as a new generation concrete in construction field. It is characterized by a silica fume-cement mixture with very low water-binder (w/b) ratio and very dense microstructure, which is formed using various powders such as cement, silica fume and very fine quartz sand (0.15~0.4mm) instead of ordinary coarse aggregate. However, the unit weight of cement in RPC is as high as 900~1,000 kg/㎥ due to the use of very fine sand instead of coarse aggregate, and a large volume of relatively expensive silica fume as a high reactivity pozzolan is also used, which is not produced in Korea and thus must be imported. Since the density of RPC has a heavy weight at 2.5~3.0 g/㎤. In this study, the modified RPC was made by the combination of ternary pozzolanic materials such as blast furnace slag and fly ash, silica fume in order to economically and practically feasible for Korea's situation. The fire resistance and structural behavior of the modified RPC exposed to high temperature were investigated.

• Proceedings of the Korea Concrete Institute Conference
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• 2006.11a
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• pp.773-776
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• 2006

This experimental study is the fundamental report to use the ternary concrete. This study performed to know physical properties of ternary concrete according to replacement ratio of pozzolanic admixtures and curing temperature conjugation. To investigate Strength development properties of according to replacement ratio of pozzolanic admixtures, both fly ash replaced on portland cement in 5, 10 and 15% weight ratios and blast furnace slag replaced on the portland cement in 5, 15, 20, 30 and 40% weigt ratios was used. Also this is studied fresh and hardened concrete properties in condition of curing temperature $10^{\circ}C\;and\;20^{\circ}C$. The followings are the summary of which concluded in this study. Considering the concrete cured over 28 days compressive strength, most replacement ratios of pozzolanic admixtures were higher than plain concrete that. Compressive strength development properties of ternary concrete according to curing temperature conjugation were similar except for early age.