• Journal of the Korea institute for structural maintenance and inspection
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• v.6 no.1
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• pp.141-147
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• 2002

국내 주거의 주종인 아파트의 구조형식은 벽식 철근콘크리트조로 경제성 때문에 대부분 고층으로 지어지고 있다. 철근 콘크리트구조 건물을 구체공사비중 상당부분이 거푸집공사에 투입되고 있다. 구체공사의 공기(工期)는 층당 소요일수로 산정할 수 있는데 공사비 절감 및 공기단축을 통한 시공효율상의 향상을 위해서는 지주시스템의 효율적인 전용(轉用)이 필수적이라 할 수 있다. 본 연구에서는 벽식구조 아파트의 현장조사를 토대로, 현재 사용되고 있는 지주시스템 및 바닥슬래브에 대한 응력해석을 수행하고, 이를 분석하여 공기단축의 가능성을 검토하였다.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• autumn
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• pp.416-421
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• 2001

The domestic reinforcement concrete works have mainly worked the process of re-bar fabrication/assembly on site and re-bar works affected by structural safety, durability, and schedule with form work. Accordingly, This study analyzes the process of re-bar fabrication/assembly on site to apply lean production principles to construction Value Stream Analysis(VSA) is analyzed into value-adding activity and non-value-adding activity on construction process through value analysis and Value Stream Mapping(VSM). In the results, non-value-adding activity generates waste such as the activity steps, labors, equipments, materials, time, and so on. Additionally, push-driven production is investigated making low productivity from the overproduction and so on. To resolve the problems in the process, The purpose of this paper eliminates waste factor through maximizing the value-adding activity generating value added and minimizing non-value adding activity. Particularly, it makes flow production and pull-driven production through minimizing work-in-process(WIP ).

• Journal of the Korea Institute of Building Construction
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• v.10 no.6
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• pp.7-17
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• 2010

Modern construction technology has been highly systemized, which has simplified the construction methods applied to construction sites. However, on reinforced concrete construction sites, there have recently been many new disasters, and these have been bigger than before due to the heavy dependency on manpower. This study investigates the cause and cases of disasters during reinforced concrete construction. In addition, the study surveyed the psychological condition of construction site personnel in relation to the safety awareness and the causes of disasters, while deriving the basic components related to disasters on construction sites in order to analyze the relationship between each component to suggest an efficient safety management measures checklist. Construction site personnel should utilize the results drawn from this study as a disaster prevention tool to use in a safety education class, and not consider this simply as statistical data, but as a checklist to ensure full awareness of the appropriate priorities for safety categories to utilize in the reinforced concrete construction in order to execute reasonable safety management.

• Journal of the Korea Institute of Building Construction
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• v.8 no.2
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• pp.71-79
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• 2008

The rebar work is very related to the safety and durability of the building. Recently, the rebar work is produced some serious problems due to the lack of skillful crafts-man and the rising cost of rebar materials. Many papers have dealt with the rebar work of the manufacturing system in plants with a view to improvement those problems. But, the research on the rebar work of the manufacturing system in field is in a insignificant condition. This study presents the following improvement schemes as a result. First, the education strengthening for evaluation on practical affairs, second, the reinforcement of drawing & management in shop drawing and finally the simplification of apartment rebar work in slab. Also, this paper aims at advancing apartment rebar work by the actual condition survey in slab work. The further research will be needed about the whole structure parts such as foundation, wall, girder and rebar truss-deck plate as one of the improvement methods.

• Journal of the Korea Institute of Building Construction
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• v.5 no.4 s.18
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• pp.153-164
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• 2005

This study aims at establishing JIT production management system to enable manage the resources input into from procurement through construction based on correct identification of the process, an analysis on the amount of input materials and information sharing. This study has focused on the process control and working process of rebar work in domestic apartment house construction where the overall scope of Process from the planning phase to the construction phase has been analyzed in this study. Also construction phase was selected for the application of a sample case. A basic model for JIT production was generated with these processes. Furthermore A questionnaire and the on-site survey with process, checklist and control data were prepared and performed for the application of JIT production management model into rebar work. The governing scopes of JIT production management system include process management, material management, yard loading and moving management and inventory control, and the operation of each control item

• Proceedings of the Korean Institute of Building Construction Conference
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• 2010.05a
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• pp.165-166
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• 2010

In this study, it was accomplished to analyze the productivity and manpower through the activity of rebar work for the application of rational construction cost in apartment house. And the rebar work is very important in the view of the expense and safety, and durability in the construction of R/C structure. Also the rebar work is very affected with productivity owing to the lack of manpower and materials cost rise.

• Journal of the Korea Institute of Building Construction
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• v.4 no.3
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• pp.83-91
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• 2004

With labor shortage and high-wage era, the construction cost is rising and the construction business is dull, demanding the construction environment of Korea to raise profitability through major cost savings and rationalization of construction management. However, although reinforcing bar(rebar) work, which greatly effects the building's safety, endurance, and construction time, is an important phase in construction, it holds serious problem of quality and productivity deterioration due to its characteristic of intensive-labor and maintaining of old work methods resulting in poor management, and costs increase. Therefor in this study to investigate current situation and problems of rebar work and to find methods of betterment, a survey was conducted to site engineers and individuals in division of cost estimate of domestic construction company. The survey questions were on the subjects of (1) calculating rebar quantity, (2) ordering and procurement, (3) rebar cutting and bending, and (4) rebar work management. Method of improvement was sought by analyzing the results of the survey

• Journal of the Korea institute for structural maintenance and inspection
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• v.20 no.4
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• pp.120-127
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• 2016

Due to the enlargement and high-rise of reinforced concrete structure, the application of high functional material is required. However, high-strength bar is recently introduced to the country and the material is insufficient to measure the variation of quantity of rebar quantitatively when using high-strength bar. For these reasons, this study is to provide useful data in cost decision making when applying high-strength bar at a stage of architectural project planning. For residence-commerce complex buildings, we set up six types of conditions such as in case of using only rebar, in case of using only high-strength bar, in case of using rebar mixed with high-strength bar and so on. With the standard of study model 1 that applies only SD400 regardless of rebar diameter, the analyzed result of rebar variation and the cost change of construction in other study model is as follows. When the rebar amount and cost in study model I was 100%, each ratio was 88.3% and 90.5% in study model II, 80.2% and 83.4% in study model III, 91.9% and 93.5% in study model IV, 88.9% and 87.7% in study model V and 82.4% and 85.5% in study model VI. Therefore, in case of rebar amount and construction cost, study model III was evaluated as the best that was applied only SD600.

• Proceedings of the Korean Institute of Industrial Safety Conference
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• 2002.05a
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• pp.109-114
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• 2002

건설공사의 공종 중 거푸집공사는 전체공사기간의 대략 25％를 차지하고 있으며 공사비 비율은 일반적으로 전체공사비의 10～15％, 철근콘크리트공사비의 20～30％를 차지하고 있어 구조물의 안전성, 경제성 및 작업성과 품질관리에 중요한 역할을 한다. 또한 거푸집은 콘크리트가 양생되면 곧 해체되는 가설구조물로써 작업상에서 많은 위험요소를 포함하고 있으며 특히, 아파트공사의 경우 전체 재해발생의 17％로 가장 높은 비율을 차지하고 있다. 이와 같이 거푸집공사는 가장 우선적으로 관리하여야 할 위험공종이며 전체공기를 좌우하는 주공정으로서 이를 재해발생의 측면에서 제어하는 것이 안전관리에 있어서 가장 효율적이며 큰 효과를 나타낼 수 있는 것으로 생각된다.(중략)

• Journal of the Korea Institute of Building Construction
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• v.19 no.6
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• pp.521-527
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• 2019

Quantity takeoff and cost estimates in Korea are carried out in practice without any clear standards or standards. Especially, quantity takeoff of Reinforcing bar and BoQ documentation process is very complex using 2D drawings. In this study, 10 case sites were analyzed for the status of inefficient quantity takeoff and how the statement was prepared. In order to solve this problem, this study presented a method for calculating the quantity of rebars through the ratio of concrete volume for schools, offices, and apartment buildings, and analyzed the accuracy of results. In the future, it is expected that the error range can be reduced by defining the factors affecting the results and calculating the correction value for them.