• 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.

• Journal of the Korea Institute of Building Construction
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• v.2 no.4
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• pp.163-168
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• 2002

The object of this study is to define the characteristics of high performance concrete with varing compressive strength of concrete and curing temperature. The major test variables are 1) high strength concrete(500kg/$cm^2$) and ordinary strength concrete(240kg/$cm^2$) compressive strength, 2) curing temperature and condition, 3) concrete curing age, 4) three types of cement. From the test results were shown that curing temperature and curing conditions were also very effective for high strength concrete and ordinary strength concrete, and concrete were largely effected by cement type and temperature during the hydration reaction process. This paper describes the effect of curing temperature for strength and characteristics of high performance concrete.

• Composites Research
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• v.19 no.1
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• pp.43-48
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• 2006

High performance fiber reinforced cement composites have better performances than traditional cement based materials, therefore, have been expected as new construction applications such as the materials for construction & bridge structure, repair and rehabilitation applications, anti-collapse applications, anti-noise applications etc. However, they have lots of the problems such as material design, fabrication method and structural analysis. Also, the most serious problems of High performance fiber reinforced cement composites have been expensive initial cost, lack of long-term exposure data. As a result, it is needed that the efforts for lowering the initial cost and accumulation of long-term exposure. There has been hardly assessment results of life cycle cost for HPFRCC in construction field, but some papers showed that total life cycle cost could be profitable if the initial cost could be reduced.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2016.10a
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• pp.89-90
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• 2016

In the cold-weathering(Mongolian region) concrete construction, this purpose of this research is the evaluation on the performance of concrete using various binders such as Mongolian cement, Chinese cement and high blane-self heated cement.

• Advances in concrete construction
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• v.1 no.2
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• pp.151-162
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• 2013

The performance characteristics of high-strength and high-performance concrete are discussed in this review. Recent developments in the field of high-performance concrete marked a giant step forward in high-tech construction materials with enhanced durability, high compressive strength and high modulus of elasticity particularly for industrial applications. There is a growing awareness that specifications requiring high compressive strength make sense only when there are specific strength design advantages. HPC today employs blended cements that include silica fume, fly ash and ground granulated blast-furnace slag. In typical formulations, these cementitious materials can exceed 25% of the total cement by weight. Silica fume contributes to strength and durability; and fly ash and slag cement to better finish, decreased permeability, and increased resistance to chemical attack. The influences of various mineral admixtures such as fly ash, silica fume, micro silica, slag etc. on the performance of high-strength concrete are discussed.

• 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.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.05a
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• pp.179-180
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• 2015

Recently, admixture manufacturers have improved the performance of admixtures to solve problems caused by high viscosity of high performance admixtures, and accordingly, it is expected to affect fluidity of concrete using admixtures. Therefore, in this research, how each kind of HAE affects consistency curve of cement mortar was examined.

• Journal of the Korea Concrete Institute
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• v.15 no.5
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• pp.739-746
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• 2003

Various researches on the application of polymer dispersions to the cement mortar and concrete have been carried out in many countries like America, Japan and Germany and so on due to their high performance and good modification effect. PAE of polymer dispersion widely used in situ was employed that the high flowability may be induced in the cement mortar. In order to investigate the modification of cement mortar with high flowability by PAE and fracture mode of adhesive strength properties in tension of that, experimental parameters were set as PAE solid-cement ratio(P/C) and cement: fine aggregate(C:F) and the experiments such as unit weight, flow, consistency change, crack resistance and segregation that inform on the general properties have been done. Adhesion in tension is measured with a view to comprehending the properties and fracture mode in tensile load. Consistency change of cement mortar modified by PAE did grow better as the ratio of PAE solid-cement increased and was much superior to that of resin based flooring such as polyurethane and epoxy which recorded the loss of consistency in 90 min. after mixing. Adhesive strength in tension increased with continuity during curing period and showed the maximum in case of C:F=1:1 and P/C=20%.

• Journal of the Korean Ceramic Society
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• v.33 no.5
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• pp.519-523
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• 1996

Calcium hydroxide produced by cement hydration decreases the durability and the compressive strength of cement mortars. Pozzolanic property of meta kaolin and silica fume allows to avoid this drawback. Calcium hydroxide consumption according to pozzolanic raction is evaluated by Fourier differential thermal analysis. Particulary the properties of high performance and high strength of cement mortar containing above 10% meta kaolin and silica fume were resulted in the pozzolanic activity.

• Proceedings of the Korea Concrete Institute Conference
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• 1998.04a
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• pp.171-176
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• 1998

Recently, the Belite cement having the high fluidity, high strength, and low heat properties, was developed, and is being promoted the efforts for application on the real structures. Accordingly, for the purpose of practical use of high strength concrete using the Belite cement, was carried out the performance evaluation experiments about the structural members(column, beam, column-beam joint, steel bond strength etc.). Specimens were made in three types of concrete(Belite:350, 600kg/$\textrm{cm}^2$, OPC:350kg/$\textrm{cm}^2$) by taking into account the key parameters. In this paper, were summarized the comparative experimental results on the material properties and structural performance of Belite concrete.