• Journal of the Korea Institute of Building Construction
• /
• v.13 no.6
• /
• pp.627-633
• /
• 2013

This paper presents the result of a mock-up test and field application of concrete that is black in color thanks to the application of superplasticizer containing carbon amino silica black (CASB-SP). Mock-up specimen with a size of $3000{\times}1500{\times}40$ mm was fabricated with black concrete applying 0.5% of CSAB-SP with 27 MPa. After dividing the zone in wall mock-up specimen, three different water repelling agents were applied to verify its effect of efflorescence prevention. It was found that the use of CASB-SP with 0.5% made the black concrete develop a highly clear black color, and the epoxy type water repelling agent had better performance in efflorescence prevention. Based on mock-up test, field application was conducted with bridge member. It was also found that the application of CASB-SP showed favorable results in black color development.

• KIEAE Journal
• /
• v.10 no.6
• /
• pp.131-137
• /
• 2010

This study aims to know temperature and humidity handling ability of Hwang-To brick and traditional paper window's in mock-up room test. To achieve these goals, mock-up room test was carried out. The results are as follows. 1) There are no significant differences among specimen in temperature handling capacity. 2) Traditional paper windows are very sensitive when compared with glass window in humidity control. 3) Traditional paper windows have a big handling capacity in humidity control when vapors letting out in mock-up room. 4) Hwang-To brick case is more stable than other cases in relative humidity variances because it has more potential to contain humidity.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2008.11a
• /
• pp.1-5
• /
• 2008

In this study, batcher plant composition test and mock-up test were carried out to conduct comparison and analysis on flow behavior and strength properties of concrete at early age. As a result, it was found that slump and amount of air in batcher plant composition test reached the target range. As for compressive strength, composition using HESPC showed the most excellent strength development. In mock-up test which was carried out to find out the strength properties, two methods with specimen and core test body both revealed HESPC as the most excellent composition. However, strength estimation with ultrasonic survey presented less reliable data. As a result of the previously conducted indoor composition test and the mock-up test in this study, target performance of concrete at early age was 4day/cycle. It was found that the optimum conditions that meet the required strength, 5MPa/18hr and 14MPa/36hr in mullion and transom are; curing temperature above 15℃, W/B 45%, unit-water 165kg/㎥ and CHC cement.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2009.05a
• /
• pp.223-224
• /
• 2009

This study was performed to development 80MPa high strength concrete using local raw material of Busan and to estimate field application ability. As the result of three types of mixture, fresh and hardened properties were satisfied with target requirement properties. Hydration temperature was revealed mean 75$\sim$85$\circ$C. Additionally, in case of compressive strength, core specimen's strength is six times higher than field curing specimen by very high hydration heat.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.25 no.6
• /
• pp.185-192
• /
• 2021

In this study, Full-scale hollow slab Mock-up with VPS(Void Plywood Slab System) was produced. Through Mock-up, the safety of the flat plate hollow slab against short-term sagging and long-term sagging is to be evaluated. The hollow rate of the mock-up specimen to which the hollow core slab was applied was designed to be 24%. When loading through concrete blocks, the most central part of the slab was deflection 8.88mm when loading. However, it shows a safe value compared to the reference value (l_n/240=17.93mm) for short-term deflection. As a result of 3 months of measurement of the mock-up experiment, the deflection at the center of the slab increased by 6.792mm from the initial deflection. In addition, it was found that the reference value by the load used suggested by KBC2016 was satisfied.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2014.05a
• /
• pp.134-135
• /
• 2014

In this study, mock-up test for high strength concrete with ERCO has been carried to analyse the effect of autogenous shrinkage reducing of using ERCO. The following results could be made as the conclusion. Results of EIS were lower than 2.5 and showed good resistance for separation of materials. For the setting time, specimen with ERCO showed delay of setting comparing with Plain. For the autogenous shrinkage, as the generation of saponification, capillary pores inside the concrete were filled by soap and the autogenous shrinkage has been obviously decreased. It could be identified that using ERCO in high strength showed good effect on reducing autogenous shrinkage in high strength concrete.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2021.11a
• /
• pp.148-149
• /
• 2021

In Japan, ultra-low shrinkage concrete has been developed and commercialized to control drying shrinkage cracks to the limit. However, in the case of South Korea, the study on this technology has not yet been conducted in earnest. Therefore, the study was conducted for the development of ultra-low shrinkage concrete to control the drying shrinkage crack of concrete to the limit, and in this study, after determining the mixture of ultra-low shrinkage concrete, a wall type mock-up specimen was produced to observe the shrinkage behavior of ultra-low shrinkage concrete.

• Journal of the Korea Concrete Institute
• /
• v.25 no.2
• /
• pp.195-200
• /
• 2013

New thermal crack control system for mass concrete was developed to increase quality and to save construction period and cost. The principle of this system is that the curing water having proper temperature is supplied automatically to the surface of mass concrete member to keep the temperature difference between center and surface of concrete less than generally recommended temperature difference ($20^{\circ}C$). Mock-up test was conducted to investigate the validity of newly developed curing system. As a result, no crack was founded in the specimen using automated curing system developed in this study, while many cracks occurred in another specimen without automated curing system. It was also confirmed that the strength and the durability of the concrete cured by automated curing system were improved.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.10 no.5
• /
• pp.106-114
• /
• 2006

This paper investigates the fundamental properties and shrinkage characteristics of low shrinkage high performance concrete(LSHPC), using mock-up specimens. According to the test results, the most suitable mix proportions of LSHPC need a higher dosage of SP agent and AE agent, in order to obtain the target of slump flow and air content. This is due to reduce fluidity and air content respectively. It also presented earlier setting time than control concrete by 6 hours and exhibited compressive strength of 60MPa at age 28 days. Autogenous shrinkage of LSHPC was the half of the value of control concrete. Drying shrinkage of center section of LSHPC showed similar tendency with autogenous shrinkage, because of no internal moisture movement, while surface section had larger drying shrinkage. The specimen with embedded reinforcing bar had smaller deformation owing to confinement of reinforcing bar.

• Journal of the Korean Recycled Construction Resources Institute
• /
• v.5 no.1
• /
• pp.59-67
• /
• 2017

The objective of this paper is to investigate experimentally the effect of replacement of recycled coarse aggregates with 5~13mm in size on a field applicability of concretes through Mock-up test. Seven different mock-up specimens were prepared with the size of $1200{\times}800{\times}800mm$ simulating column and wall. For the concrete mixtures, 24MPa, 27MPa and 40MPa of nominal strength were adopted with 30% and 70%(only for 24MPa) of 5~13mm recycled coarse aggregate (RCA) replacement and without 5~13mm RCA(Plain). For test items, slump, slump flow, compressive strength with different curing conditions, core drilling, rebound numbers and drying shrinkage were measured. Test results indicated that 30% of 5~13 mm RCA replacement resulted in increase in slump, slump flow and resistance against segregation, while air contents decreased compared to those of plain mixture. Compressive strength of concrete with 30% of 5~13mm RCA was shown to be higher than that of plain mixture due to optimum packing effect associated with presence of well graded aggregates. Rebound number of the mock-up specimen with 30% of 5~13mm RCA had lower fluctuation according to hitting location than that of plain mock-up specimen. It is believed from the results of the study that replacement of 30% of 5~13mm RCA brings desirable improvement in various aspect of concrete performance due to associated dense packing effect.