• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.3
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• pp.180-187
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• 2014

The purpose of this study is to evaluate on the mechanical properties of High Volume Mineral Admixture(HVMA) high strength concrete to reduce the amount use of Ordinary Potland Cement, to discover the optimized HVMA binder and to test HVMA concrete based on the change of W/B and curing temperature. The results were shown as follows: The HVMA binder using the mixture of combined heat power plant fly ash and anhydrous gypsum known as inorganic activators with the mixture of blast furnace slag and fly ash was optimized. The mixture of HVMA high strength concrete at 26% of W/B ratio had a good result on flow characteristic and mechanical properties. High strength HVMA concrete over 50MPa is possibly manufactured over curing temperature $20^{\circ}C$.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.4
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• pp.354-359
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• 2014

The objective of this study is to examine the fatigue behavior in compression of normal-weight and lightweight concrete mixtures with high volume supplementary cementitious material(SCM). The selected binder composition was 30% ordinary portland cement, 20% fly-ash, and 50% ground granulated blast-furnace slag. The targeted compressive strength of concrete was 40 MPa. For the cyclic loading, the constant maximum stress level varied to be 75%, 80%, and 90% of the static uniaxial compressive strength, whereas the constant minimum stress level was fixed at 10% of the static strength. The test results showed that fatigue life of high volume SCM lightweight concrete was lower than the companion normalweight concrete. The value of the fatigue strain at the maximum stress level intersected the descending branch of the monotonic stress-strain curve after approximately 90% of the fatigue life.

• Journal of the Korea Institute of Building Construction
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• v.13 no.3
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• pp.282-290
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• 2013

In this study, the adjustment range of mixture factor with replacement mineral admixture was reviewed to secure the mixture change data of high volume concrete compared to general concrete. When changing the concrete mix to high volume concrete within the universal concrete mixing, the adjustment range of mixture to ensure optimum quality is as follows. Unit-water content is $20{\sim}30kg/m^3$ downward. Fine aggregate ratio dropped by approximately 1% when W/B was reduced by 5%, and it is reduced by approximately 0.12% when there is a 5% increase in the total replacement rate. When the FA replacement rate was increased by 5%, the AE agent was approximately 20% to 30% higher compared with the conventional one. When the FA and BS replacement rate rose by 5%, W/B was reduced by about 1 to 4%.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.2
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• pp.93-100
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• 2013

A variety of researches on the concrete with high volume mineral admixture have increased in recent years. In fact, it is very important to find appropriate replacement ratio of concrete with high volume mineral admixture in order to apply in the field. In this study, compressive strength according to fly ash and blast furnace slag replacement ratio as well as curing temperature was measured in the conditions of obtaining the same workability in order to examine the characteristics of concrete with high volume mineral admixture. In conclusion, it was found that the compressive strength at the age of 3 days decreased by 1.4MPa and the compressive strength at the age of 28 days decreased by 3.8MPa when the fly ash replacement ratio increased by 10%. Also, it was found that the compressive strength at the age of 3 days decreased by 1.0MPa and the compressive strength at the age of 28 days decreased by 0.9MPa when the blast furnace slag replacement ratio increased by 10%. Through the tests, we obtained the basic data for developing the future research on the concrete with high volume mineral admixture for housing structure.

• Journal of the Korea Concrete Institute
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• v.27 no.6
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• pp.641-649
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• 2015

The purpose of this study was to assess the durability of high-strength concrete with high volume mineral admixture (HVMAC) derived from previous studies within ternary blended concrete (TBC) and normal concrete (NC). Four durability evaluation types such as chloride penetration resistance, freezing and thawing resistance, carbonation resistance in two pre-treatment conditions, and sulfuric acid and sulfate resistance using 5% sulfuric acid ($H_2SO_4$), 10% sodium sulfate ($Na_2SO_4$), and 10% magnesium sulfate ($MgSO_4$) solution were selected and performed in this study. HVMAC showed the excellent chloride penetration resistance in any age and the freezing and thawing durability close to 100%. In addition, HVMAC affected more reduction in carbonation resistance than TBC. When the curing time was increased, to create a concrete internal organization densely improved resistance to carbonation. HVMAC also showed the most superior in sulfuric acid and sulfate resistance. As the reduction of calcium hydroxide and $C_3A$ to apply a large amount of admixture reduced the swelling and cracking of concrete, the strength reduction and mass change of concrete was found to be small indicated.

• Journal of the Korean Recycled Construction Resources Institute
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• v.6 no.2
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• pp.67-73
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• 2011

In this study, it was investigated compressive strength generation of concrete using high volume mineral admixture obtaining fundamental data for the application of concrete structure in construction field. For this, it was evaluated compressive strength with unit binder contents($310{\sim}410kg/m^3$), replacement ratio of mineral admixture(70~90%), unit water contents($140{\sim}150kg/m^3$) and curing temperature in the normal strength range. Also, after producing mock-up structure, hydration heat and compressive strength generation was evaluated to examine properties in the concrete member. In case of concrete using a large amount of industrial byproducts which was reviewed in this study, it is possible to secure compressive strength more than 24MPa at age 28days with about $13^{\circ}C$ ambient temperature of curing condition and that is considered to be applied to structure at construction site.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.134-135
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• 2015

This study analysed compressive strength and the expansion characteristic to utilize a high volume mineral admixture mortar for a aerated mortar and a plastering mortar. In this experiment, the result shows that the compressive strength gain was satisfactory in case that WR was replaced within 5%. Also, the difference between WR1 and WR was insignificant. It shows that the drying shringkage properties at large was showed being satisfactory generally compared with Plain when WR was replaced, but the effect was not significant.

• Journal of the Korea Institute of Building Construction
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• v.18 no.1
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• pp.33-40
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• 2018

Currently, in South Korea, because of reducing the construction period or treating wasted water, there are some cases of missing wet curing for concrete structure even though for high strength concrete. This air curing conditions is considered to cause increased possibility of compressive strength decrease, and increasing drying or autogenous shrinkages. As a solution of shrinkage of concrete, The authors' research team conducted the research on improving durability of concrete with decreasing autogenous shrinkage by adding the oil or fat to induce the saponification. Therefore, in this research, the influence of curing method on compressive strength, shrinkage on evaporation rate of high strength mortar including high volume supplementary cementitious materials (SCMs) was evaluated depending on various curing methods such as air curing, drying after painting emulsified refined cooking oil (ERCO), and drying after 7 and 28 days' wet curing. The experimental result showed the air curing method caused approximately 50% of decreased compressive strength and 1.9 times of increased shrinkage rather than the 28-day-wet curing method, thus it was known that the wet curing significantly influences on performance of high strength mortar using high volume SCMs. However, the ERCO painting curing caused decreased performance of concrete rather than drying after 7 days curing while it caused improved performance of concrete than entire period air curing.

• Journal of the Korean Recycled Construction Resources Institute
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• v.1 no.3
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• pp.173-180
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• 2013

This paper is to investigate an effect of waste cooking oil(WCO) on the engineering properties and durability of high volume admixture concrete. Fly ash with 30% and blast furnace slag with 60% were incorporated in OPC to fabricate high volume admixture concrete with 0.5 of W/B. Emulsified refining cooking oil(ERCO) was made by mixing WCO and emulsifying agent to improve fluidity. ERCO was replaced by cement from 0.25 to 1.0%. As results, the increase of ERCO resulted in decrease of slump and air contents. For compressive strength, the use of ERCO led to decrease the compressive strength at 28 days, while it had similar strength or much higher strength than plain concrete at 180 days. Resistance to carbonation and chloride penetration was improved with the increase of ERCO contents due to decreased pore distribution by saponification between ERCO and concrete, while freeze-thaw resistance was degraded due to air loss.

• Journal of the Korean Recycled Construction Resources Institute
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• v.2 no.3
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• pp.247-254
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• 2014

The present study prepared lightweight foam-soil concrete mixtures classified into three groups. Considering the sustainablility, workability, and compressive strength development of such concrete, high-volume supplementary cementitious materials (SCMs) were used as follows: 20% cement, 15% fly ash, and 65% ground granulated blast-furnace slag. As main test parameters selected for achieving the compressive strength of 1MPa and dry density of $1,000kg/m^3$, the unit solid content (dredged soil and binder) ranged between 900 and $1,807kg/m^3$, and soil-to-binder ratio varied between 3.0 and 7.0. Test results revealed that the flow of the lightweight foam-soil concrete tended to decrease with the increase of unit soil content. The compressive strength of such concrete increased with the increase with the unit binder content, whereas it decreased as soil-to-binder ratio increased, indicating that the compressive strength can be formulated as a function of its dry density and soil-to-binder ratio.