• Journal of the Korea Institute of Building Construction
• /
• v.2 no.4
• /
• pp.39-49
• /
• 2002

• Journal of the Korea Institute of Building Construction
• /
• v.2 no.4
• /
• pp.50-54
• /
• 2002

• Proceedings of the Korea Concrete Institute Conference
• /
• 2008.04a
• /
• pp.601-604
• /
• 2008

When the concrete is placed, the water, needed for hydration of the cement, is under 30% of W/C including bound and gel water. However, as minimum water content cause bad workability, the W/C have to be higher. Therefore, fresh concrete produce 10${\sim}$20% extra water. As those water remain entrapped air in the concrete, life of the structure is reduced because of the degradation caused by entrapped air. For that reason, if extra water is eliminated, it will be great to improve the durability of the structures. Therefore, this study was performed to verity the fundamental properties through the experiment on the dewatering system using the euro form for eliminating extra water. When the dewatering form was applicated, the compressive strength was increased by 16% than those of normal form. However, the increasing rate of compressive strength got lower as the height is higher. In terms of ultrasonic pulse speed and surface roughness, the dewatering form showed better results than the normal one.

• Korean Journal of Construction Engineering and Management
• /
• v.2 no.3 s.7
• /
• pp.101-109
• /
• 2001

Application of system form is very effective to continuous horizontal or vertical walls of the apartment housing. Though the system forms that are used in the construction field have the advantage of concrete quality improvement and increasing number of usages, there are some problems in reaching early planning scheduling goal due to schedule delay and low productivity. This study is initiated to solve the problem and suggest some improvements searching for reasons that diminish the productivity. A case study was done in apartment construction field where system form was used and the productivity is analyzed by work sampling. Finally, productivity improvements for assembly of the form, internal form and external form are suggested, respectively.

• Magazine of the Korea Concrete Institute
• /
• v.14 no.5
• /
• pp.31-38
• /
• 2002

최근 환경문제에 대한 일반인의 관심고조와 함께 3D 기피현상에 따른 철근공, 거푸집공 등의 기능노동자의 부족, 고령화, 외국인노동자 고용 현상과 낮은 노동생산성은 건설업계의 심각한 현안이다. 과거에는 재료비의 비중이 높았으므로 재료의 낭비를 줄이기 위한 합리화가 추진되었다. 그러나 현재는 노무비 비율의 급격한 증대로 인하여 공기단축이나 합리화, 시스템화를 통해서 경쟁에서 생존해 나가고 있다. 건축공사 중 특히 철근 콘크리트공사는 기술의 발전이 느리고, 시공 방법도 과거의 공법을 그대로 유지하고 있는 실정이다. 건축공사비 중 구체공사의 비율은 30% 정도이고, 그 비용 중 인건비가 50% 정도를 차지하고 있기 때문에 철근 콘크리트 공사는 아직도 기술 집약적인 산업이 아닌 노동 집약적 산업으로 간주되는 결과를 초래하고 있다.(중략)

• Journal of the Korea Institute of Building Construction
• /
• v.2 no.4
• /
• pp.183-190
• /
• 2002

• The Journal of the Korea Contents Association
• /
• v.12 no.8
• /
• pp.366-372
• /
• 2012

In most of construction work, especially mat foundation construction, it is very important that accidents be prevented at early aged construction stage. To reduce the risk of accidents, it is necessary to choose the curing method to provide instructions for safety forming work by proper curing of concrete after placing. Therefore, this paper has proposed a designation algorithm of curing method for representing curing type and period by analyzing the transient hydration heat solution, focusing on mat foundation construction. This has been implemented, moreover, using an object oriented programming language to develop structural analysis system taking account crack index. In addition, we present in this paper a safety curing management system developed to assess risk during forming work.

• Korean Journal of Construction Engineering and Management
• /
• v.13 no.1
• /
• pp.53-66
• /
• 2012

Gangform compared with conventional wood and steel form is systemized form which has a capability to install and dismantle form at a time without repeating to assembly and disassembly small members. Gangform compared with ACS has some problems such as 1) Tower Crane load increase, 2) increase in safety incidence during climbing Gangform, 3) decrease in detachment operation productivity, 4) stop work due to climate impacts, and 5) decrease in labor cost, productivity, quality. A conceptual design model of automated Gangform climbing system is suggested for apartment housing construction to show its technical/economic feasibility and workers' safety while increasing operation productivity and concrete quality.

• Journal of the Korea Institute of Building Construction
• /
• v.11 no.2
• /
• pp.116-126
• /
• 2011

Recently, eco-friendly energy has been employed in diverse fields of industry in order to reduce environmental pollution and secure a new growth engine. In particular, practical applications of photovoltaic energy, such as building integrated photovoltaic systems, have been implemented to the construction industry based on the extensive interest in photovoltaic power as an unlimited and sustainable energy. While the construction of a high-rise building requires large amounts of energy, methods of reducing energy consumption in the construction phase have rarely been studied. Based on this motivation, the research proposes a photovoltaic based formwork system (PVFS), and then performs a design and feasibility analysis for its application to the construction of a high-rise building. Using a case study, the research implements various analyses, including area, position, and total allowable weight required by PVFS, and evaluates the influences of PVFS on the construction processes, as well as its economic feasibility. The proposed PVFS can be adopted to a real-world project in the near future, depending on the advancement of technology and economic feasibility. The results of this research will contribute to establishing a construction environment that promotes a reduction of energy consumption by using eco-friendly energy in the construction phase.

• Journal of the Korea Institute of Building Construction
• /
• v.17 no.2
• /
• pp.127-134
• /
• 2017

In this study, moist curing equipment was used in the exist gang-form system. By achieving sufficient spray curing, the quality of the concrete was improved and the cracking occurred in building's side wall was decreased. The following results could be made as the conclusion. For the compressive strength, all zones showed the similar results. Comparing with the zone without using moist curing equipment, the zone used moist curing equipment showed higher rebound hardness results. For the cracking, the zone utilized moist curing equipment showed the cracking averaged as 6.6 m and the zone without using moist curing equipment showed the cracking averaged as 10.3m. The effectof reducing cracking by utilizing moist curing equipment is about 36 %. Using moist curing equipment is considered as a good solution to reduce the cracking in the structure. Considering all the factors analysed, using moist curing equipment improved the quality of the concrete and decreased the cracking. When this equipment was used in the construction site, it is expected that the construction periodcan be shrunk and the ratio of defect caused by drying shrinkage can be decreased. In this research conditions, The 0.3mm sized moist curing equipment provided the most desirable results on concrete quality and preventing cracking.