• Proceedings of the Korean Institute Of Construction Engineering and Management
• /
• autumn
• /
• pp.527-530
• /
• 2002

The purpose of this study is to present an improvement of the form work process. The current slab form work has waste factor by unnecessary process and not complete integration with the finishing process. Therefore the study used value stream analysis methodology for effective improvement of slab form work process. The main contents of the study are as follows; 1) Understanding of non-value adding activities in existing slab form work process 2) Process integration by value stream mapping 3) Effect analysis of time-cost reduction. The study recommends that, as a future research, development of tool and technique for the non-value adding activities are eliminated in building construction.

• Journal of the Korea Institute of Building Construction
• /
• v.24 no.2
• /
• pp.261-271
• /
• 2024

The widespread adoption of aluminum slab formwork in modern construction, evident in both domestic and international projects, offers numerous advantages. However, a critical challenge persists regarding the dismantling process for these slabs. The current industry standard involves dropping the slabs to the ground floor upon removal. This practice raises several concerns, notably the generation of significant noise pollution that disrupts nearby communities. More importantly, the risk of worker injuries due to falls from height during the dismantling process is a serious safety hazard. Additionally, the impact from dropping the slabs can damage the aluminum itself, leading to increased replacement costs. These drawbacks necessitate the exploration of alternative dismantling techniques that prioritize worker safety, material sustainability, and overall process efficiency. Accordingly, in this study, when the entire first-generation slab formwork of an apartment house is simultaneously lowered to a reachable position for workers, it is then disassembled and lifted for transport to the next floor. This approach has the potential to demonstrate improvements in safety, quality, economy, and process efficiency.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2009.11a
• /
• pp.9-13
• /
• 2009

Recently, construction in downtown is often done closely at the adjacent building. In this case, underground construction need to Basement Composite Wall(BCW) construction. However, generally, during the construction process of BCW form works have many problems that are narrow working space and inefficient time consuming. Despite of these problems, there was no quantitative research for the work time of BCM assembly. Therefore, in this study, work time of CBW form assembly in underground construction is identified by the work analysis. The results of this study reveal that buttress work of basement form take lots of time in the entire work process of Basement Composite Wall form assembly.

• Journal of the Korea Institute of Building Construction
• /
• v.17 no.6
• /
• pp.587-594
• /
• 2017

The construction industry generates the greatest number of disasters. Laborer injury at construction sites is mostly reported by small and mid-sized construction sites. Moreover, of the injuries, the greatest number is related to formwork. The objective of this study is to propose a checklist of the risk factors of formwork, in which industrial injuries occur most frequently in small and mid-sized construction sites, with which safety management can be done thoroughly. Risk factors and preventive measures are derived by analyzing 9,396 industrial disasters occurring at construction sites in Korea. The checklist drawn in this study was reviewed by five specialists in safety management, and applied to construction sites to verify its applicability. In a result, applying the checklist to the site showed that the safety management system of small and medium-sized construction sites were insufficient. It is expected to contribute to the effective safety management of small and mid-sized construction sites.

• 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.4 no.1 s.13
• /
• pp.114-121
• /
• 2003

The precise quantity of materials is not yet taken off by the CAD system although it has Influenced in design productivity and automatic estimate. And various estimate systems developed so far deal with the quantity take-off of building members separately, which caused to over-estimate the part of each member. Therefore, the purpose of this paper is to develop algorithms of more precise estimate than that of current estimate by solving boundary conditions of the connection parts of building members, such as column, girder, beam, wall and slab. The algorithms are proposed to take off the quantity of concrete and form work and they will be used for the estimate of building structure more precisely and automatically than ever.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2023.05a
• /
• pp.213-214
• /
• 2023

Positioning information of workers is important for safety management at construction sites. Among the various indoor positioning technologies, geomagnetic fields-based technology is more economical and has less error than other technologies. However, there is a problem that the installation and dismantling of materials such as formwork at construction sites can cause degradation in positioning performance. Therefore, in this study, the distortion of the geomagnetic field near euro-form was quantitatively measured and the application method of geomagnetic field-based indoor positioning technology on formwork stage was presented. The results showed that the distortion occurred within 10cm of the wall and column form, but positioning accuracy could be affected up to 60cm from the form due to the characteristic of geomagnetic field-collecting technology. Therefore, applying this technology to the formwork stage requires complementary measures, such as using other positioning techniques up to 60 cm near the formwork, or excluding distorted area when positioning. It is expected that this study can contribute to the efficient safety management of workers by suggesting ways to prevent an increase in positioning error when applying geomagnetic field sequence-based indoor positioning technology during the formwork stage.

• Korean Journal of Construction Engineering and Management
• /
• v.3 no.4 s.12
• /
• pp.93-103
• /
• 2002

The reinforcement concrete work is the work affected by structural safety, durability, and schedule with form work. The domestic reinforcement concrete works have mainly worked the process of re-barfabrication/assembly on site. Finally it have low productivity. Then this paper analyzed waste factors and the process of re-bar fabrication/assembly on site for the productivity improvement and value-added productivity improvement. Waste factor analysis aims at maximizing value-added by the value analysis of re-bar fabrication and assembly on site. Finally, Value-AddingActivity(VAA)ismuchlessthan non-value adding activity. Especially, Non-Value-Adding Activity(NVAA) generates waste such as the activity steps, labors, equipments, materials, time, and soon. And it was non-flow production, over production, and analyzed into having to shift value. This paper aimsat maximizing value-addingactivity and minimizingnon value-addingactivity through waste factor analysis in process for the improvement of value added productivity.

• Journal of the Korea Institute of Building Construction
• /
• v.16 no.3
• /
• pp.271-278
• /
• 2016

In the case of South Korea, steel girder bridge (steel box or H-steel) and PSC (Pre-Stressed Concrete) girder bridge are the representative upper structures of railroad and road bridges. These structures account for 75% of the total bridge constructions and 80% of the total construction cost. Since the form work for concreting bridge slab is difficult, various construction methods developed and applied. However, several problems in those methods did not solve partially, including cost increase by material loss and rise of labor costs, quality deterioration by unskilled workers, increased construction time by complicated method, reduced productivity, safety accident by high place work, difficult transportation by big member, and rise of maintenance cost by material characteristic. Alternative method is needed to solve problems of as-is methods. Therefore, the purpose of this study is development of the purlin hanging system form for the girder bridge slab and its economic analysis. Through the findings of this study, it was verified that the purlin hanging system form is possible 60% reduction in cost and 80% reduction in time as comparison with conventional method.

• Journal of the Earthquake Engineering Society of Korea
• /
• v.15 no.6
• /
• pp.55-66
• /
• 2011

The purpose of this study was to develop an efficient process in the design and construction of a 1:5 scale 10-story R.C. apartment building model for an earthquake simulation test. The reduction ratio of the specimen was determined by the size ($5m{\times}5m$) and pay load (600kN) of the available shaking table and the availability of model reinforcements. For efficiency and quality control of the reinforcement work, prefabrication was used. Construction was conducted in two steps, the wall in one step, and another step for the slab, because it was impossible to remove the formwork of a wall if the walls and slabs in a story were constructed in one step. The slip form construction method was used repetitively for walls. The formwork of a wall was made with veneer and acryl plate on each side, so it was possible to check the quality of the concrete placing. To construct this model, it took roughly six months with five full-time research assistants, for a total of 602 man days of labor in construction.