• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 가을 학술논문 발표대회
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• pp.127-128
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• 2020

This research is part of the research for unifying the mass concrete and utilizing the rate of super retarding agent. We analyzed the performance of super retarding agent 20℃ conditions. It was found that there was no deterioration in fluidity and air quality due to the change in the super retarding agent mixing rate. It was found that when super retarding agent was mixed up to 0.5 %, it was delayed for 22.3 hours at 20℃. Therefore in order to ensure the performance required at the site, the super retarding agent mixing rate must be determined by fully considering the situation at the site. In addition it will be analyzed that super retarding agent performance analysis at high temperature will be required in subsequent studies.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.167-168
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• 2020

In this study, we attempted to present a method for diagnosing the depth of the early frost damage concrete using organic pigments under the cold weather. As a result, it is considered that the organic pigment did not penetrate into the voids of the concrete that had been damaged by the early frost damage and only the surface was adhered. Therefore, when fine particles that can be melted in water and pass through voids are used, it is analyzed that it can penetrate damaged part of the concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.134-135
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• 2020

In this study, optimum time of drilling for injection of repair material was determined through surface stripping and cracking investigation by drilling from the 1 days to the 3 days of the age for the specimens with ∅100 mm. No surface stripping and cracking occurred on the third day of age, and the compressive strength value was above 14 MPa, which resulted in the appropriate time for drilling on the third day of age.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.146-147
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• 2020

In this study, creep deformation characteristics of high strength concrete under dry curing conditions were investigated. It was confirmed that the creep coefficient decreases as the compressive strength of concrete increases. In addition, a modified proposal for calculating the ultimate creep factor of the ACI 209 model can be derived using the measured values.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.100-101
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• 2020

This study is part of the research for improving the performance of mortar and concrete using blended slag aggregate to develope economical and high quality replacement aggregate. The characteristics of the fluidity and strength of mortar using the blended slag, which replaced the blended slag aggregate by 0, 25, 50, 75, 100% for the aggregate volume, were compared and analyzed.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.23-24
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• 2020

In this study, the concrete compressive strength estimation system Concrete IoT Management System (hereinafter referred to as CIMS) was developed, and CIMS was applied to domestic field structure slabs and wall concrete to check whether CIMS is practically available and to estimate the accuracy of the initial strength estimation of concrete. As a result, it shows a very high correlation when the compressive strength of the specimen for structural management is compared with the estimated strength of CIMS in terms of integrated temperature, and it is expected to be gradually applied to domestic construction sites in the future.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.25-26
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• 2020

In this study, by applying the concrete compressive strength estimation system Concrete IoT Management System (hereinafter referred to as CIMS) to the concrete slab concrete in the domestic field, the purpose of this study is to confirm the practical use of CIMS and to verify the accuracy of estimating the initial strength of concrete. As a result, it shows a high correlation when the compressive strength and CIMS estimated strength of the specimen for structural management are converted and compared with the integrated temperature. However, in order to determine a more accurate experimental constant, it is necessary to consider the results up to 28 days.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.191-192
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• 2020

The purpose of this study is to measure the electrical conductivity of cementitious composites as an early step to obtain shielding performance by mixing various type of steel fiber into cementitious composites, the main building material of protection facility, to shield electromagnetic pulse (EMP) damage. Fiber such as conductors as amorphous metallic fiber, hooked steel fiber, and smooth steel fiber are mixed into cementitious composites to give electrical conductivity and measure the impedance of concrete using LCR meter. By doing this, the electrical conductivity of each type of steel fiber reinforced cementitious composites (FRCC) is compared.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.195-196
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• 2020

This study evaluated the mechanical properties and alkali silica reaction of mortar according to the mixing ratio of waste glass. As a result, as the mixing ratio of the waste glass increased, the compressive and flexible strength of the mortar decreased due to the slip of aggregate, and the alkali-silica reaction(ASR) increased. So, it is considered that research is needed to prevent slip and ASR of the waste glass aggregate in order to use the waste glass as a fine aggregate for concrete.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2020년도 봄 학술논문 발표대회
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• pp.98-99
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• 2020

The objective of the study is to investigate the compressive strength of damaged part by early frost damage and sound part of the concrete placed when exposed to a low temperature of -20℃ for 24 hours in normal concrete. Test results indicated that the compressive strength of damaged part was 14.5 MPa lower than that of sounf part due to early frost damage.