• Proceedings of the Korea Concrete Institute Conference
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• 2002.10a
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• pp.561-566
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• 2002

Recently, high quality exposed concrete is needed to achieve high quality surface for outer wall of the building. In this study, to solve above characteristic of the exposed concrete we selected self compacting concrete(SCC) and compared with normal concrete. So, we developed the SCC mix design and performed the semi mock-up test. Through this result, we performed the pilot test and mock-up test to check surface of outer wall and to measure formwork pressure As a result because SCC is better than normal concrete with respect to flowability and seggregation resistance SCC is suit to a exposed concrete needed high quality surface for outer wall of the building.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.5
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• pp.487-495
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• 2005

Recently, due to the airtightness of buildings or the misuse of building materials, we have been witness SHS (Sick House Syndrome) which can have bad influences on the resident in an existing apartment house as well as newly constructed apartment house start to attract public attention. As a result of this situation, we went to restrict the TVOC (Total Volatile Organic Compound) and formaldehyde. But these guidelines concentrated on only TVOC although TVOC are consist of many individual VOC. Therefore, in this study, we will look about concentration change of VOCs (Volatile Organic Compounds) by using Mock-up test. As result of test, the concentration of four individual VOC (Benzene, Toluene, Ethylbenzene, Styrene) showed quitely low level after 7 days. On the other hand the concentration of Xylene and formaldehyde showed low level after 14 days.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.04a
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• pp.981-984
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• 2008

The super tall building above 100 floors is required that each floor's height is more than 4 meters, and each core wall's thickness is more than 60cm. Therefore, for the successive accomplishment of super tall building, the full scale mock-up test was required. The test results are as follows; Real strength of core wall was satisfied with design strength at 28 days regardless of types of strength, and according to the consolidation effect, lower part's strength was a little higher than upper part's strength. Lateral force of HSC was evaluated with max. $4.5ton/m^2$, and hydration temperature of mock-up test was evaluated that maximun heat of central part revealed about $80^{\circ}C$ at 70MPa and $65^{\circ}C$ at 50MPa, and, the difference between inner and outter part revealed about $30^{\circ}C$ at 70MPa and $12^{\circ}C$ at 50MPa. Also, no crack by hydration temperature was not shown on the surface.

• Tunnel and Underground Space
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• v.18 no.2
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• pp.107-117
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• 2008

In this study, the failure and deformation characteristics of steel fiber reinforced shotcrete (SFRS) which is a primary tunnel support was investigated to find out ground-support mutual behavior. To this end, a mock-up of a tunnel was made and experimented with the conditions of lateral earth pressure coefficient 0.5 and 1.0. During the tests, 11 hydraulic cylinders were used for loading. for better simulation of the lateral earth pressure effect, these cylinders were controlled separately by two groups; crown and side wall. Meanwhile, the deformation of shotcrete was measured by 11 LVDTs. Backfill material was also used fur better load transfer from hydraulic cylinders to shotcrete. For the validation of the mock-up test results, 3D numerical analysis is carried out. To do numerical analysis under the same condition as a mock-up test, the load history curve which was obtained during the test was tried to be simulated using an individual FISH routine in the numerical analysis.

• Journal of Technologic Dentistry
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• v.44 no.3
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• pp.104-110
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• 2022

Purpose: This study analyzes the difficulty and discrimination of the paper-based test (PBT) and the computer-based test (CBT) according to item response theory, focusing on the National Dental Technician Examination. Methods: A mock test was conducted from September 15 to 23, 2020, and the final 179 (1 out of 180 absentees)people were the subjects of this study. Both frequency analysis and factor analysis were performed. The collected data were analyzed using IBM SPSS Statistics ver. 18.0 (IBM) and jMetrik programs. The significance level was set to 0.05. Results: The difficulty of the mock test was more easily responded to in CBT. It was also predicted that the CBT could better measure the ability of test takers than the PBT could. Conclusion: The difficulty, discrimination, and reliability of the questions were not affected by the examination method through the mock test. The feasibility of a future change to the CBT was confirmed by the National Dental Technician Examination.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2011.05b
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• pp.31-34
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• 2011

In this study, for the evaluation of field application of low heat concrete using high volume mineral admixture, the characteristics of hydration heat generation and engineering properties of low heat concrete was investigated by mock-up test according to the replacement ratio of mineral admixture. Also, it was evaluated the compressive strength of low heat concrete with curing temperatures and ages for effective concrete mix design considering seasonal change.

• Proceedings of the Korea Concrete Institute Conference
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• 2000.04a
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• pp.835-840
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• 2000

The purpose of this study is developing concrete Mixing & placing method that could be adjusted to vertical joint at top-down method. Basic test was consists of general, high fluidity, and high quality mixing concretes and Mock-up test had several placing ways, placing positions. They were examined several placing ways, placing positions with Mock-up model comparison with three mixing concrete to know fluidity characterics. Used with Mock-up model to know packing ability from placing ways and positions. The result of the study like this; High fluidity and High quality concretes show favorable packing ability, especially, in sheath placing way. It was expected to good result in next planned real structure test.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.228-229
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• 2017

MOCK-UP TEST was conducted in the extreme region of the cement which was researched and developed by using the reducing slag Experimental results show that the basic properties (air volume, slump) are improved compared with the specimens using Mongolian cement. The compressive strength achieved the target strength (target strength: age 3day: 7MPa, age 7day 14MPa) and the hydration heat was about 8 ℃ higher than that of Mongolian cement products. Therefore, it is considered that the cement powders developed by our company showed the strength of concrete due to high hydration heat even at extreme temperatures.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2022.11a
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• pp.129-130
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• 2022

This study is conducted to identify improvements in the setting time estimation system through the Mock-up test of the finishing automation system and the setting estimation system. As a result of the study, it is necessary to adjust the spring strength of the setting time estimator and the diameter and length of the estimation needle so that the value of the hardness can be measured from 15HD to around 40HD.

• Land and Housing Review
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• v.13 no.2
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• pp.117-123
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• 2022

In this study, titanium dioxide photocatalyst was applied to the ventilation system to reduce particulate matter and nitrogen oxides (NOx), which are representative indoor harmful substances. A reaction device capable of installing an ultraviolet lamp was designed and manufactured so that the pollutant decomposition effect of the titanium dioxide photocatalyst identified through previous studies could be applied indoors. The reaction device was used on the indoor ventilation system and applied to the Mock-Up test. As a result of the Mock-up test, the NOx reduction performance according to the change in air volume once per hour and five times per hour was confirmed. As a result, it was confirmed that as the number of ventilation increases, the NOx reduction time decreases proportionally, and the reduction performance increases.