• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6A
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• pp.419-426
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• 2012

Fresh concrete has 10~20% extra water in it. As those water remain entrapped air in the concrete, life span of structures is reduced. For that reason, if extra water is eliminated, it will be useful to improve the durability of the structures. Though there were many reports about permeable formwork, the study on the properties of permeable liner itself has been insufficient. In addition, making holes on the form causes lowering of workability. Therefore, this study reviewed the properties of woven and non-woven permeable liner and formwork which has no holes on the form. For the woven and non-woven permeable liner, they showed great application with W/C decrease, lowering roughness, increased compressive strength of surface area and slight loss of cement paste, when the were applied to concrete. In addition, they showed different performance according to the density of woven liner or thickness of non-woven liner. Furthermore, when using the draining non-woven permeable liner which has drainage path inside, concrete surface showed required performance with high workability, without drilling the holes on the form.

• Journal of the Korea Institute of Building Construction
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• v.11 no.2
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• pp.136-144
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• 2011

The form-work operation of concrete structures is a major element determining the period and cost of construction projects. However, the selection of the appropriate form-work system is dependent on the experience of the site personnel only. In this paper, existing methods (Aluminum form, Sky deck) and new slab form-work methods (AFB: Aluminum panel Form with dropping Beam) were selected. Each method was estimated by means of Delphi techniques based on the qualitative analysis data. This paper suggests an evaluation methodology of slab form-work application in construction sites by calculating qualitative evaluation scores. The methodology finding quantified scores of qualitative criteria can be available to be applied to other construction operation evaluation methods.

• Journal of the Korea Institute of Building Construction
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• v.9 no.6
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• pp.189-195
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• 2009

Recently, the urban centralization phenomenon appears to be growing. As a result, many vigorous efforts for the use of underground space are being made. In particular, the basement depth of construction in the downtown area has deepened and construction is often done close to adjacent buildings. In this case, generally, the underground construction approach mainly used is the composite basement wall system. However, a cost analysis of the basement composite wall system does not exist. Therefore, in this study, the cost of the composite basement wall system was analyzed. The percentage breakdown of costs were: buttress work processes, 3% form work processes, 26% reinforcement work processes, 12% support work processes, 42% and other processes,17%. Accordingly, it will be necessary when developing new technology and construction methods to determine the development focus.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.2D
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• pp.159-166
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• 2012

During concrete placement, the formwork structure supports the weight of concrete mass. The complexity of the operation can cause concentrated workloads, which in turn brings about a collapse of the temporary structure. As a countermeasure, the operation needs to be constantly monitored to maintain safety and prevent accidents. This paper presents a USN (Ubiquitous Sensor Network)-based safety monitoring system for formwork construction. The system takes advantage of ubiquitous technology in monitoring the behavior of the formwork structure such as deflection, load weight, and tilting. The collected data are sent to the host computer wirelessly for real time monitoring. The data can be then compared with the allowed limits on guidelines. The comparison can indicate whether the concrete placement operation is executed in a safe condition.

• KIEAE Journal
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• v.7 no.6
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• pp.91-97
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• 2007

This research examines the characteristics of the "rammed earth form" based on the criteria for the selection of forms. For this purpose, the paper first reviews the characteristics and orientation of the earth-construction and looks into the outline, the prerequisite, the current status and the tendency of the rammed earth form system through previous studies. Consequently, we aims to contribute to the criteria for the selection of rammed earth forms in the future through a comparative analysis of the construction cost, quality, safety and easiness of works between the veneer board form and the euroform, which are most widely used at earth housing project in the domestic country. The results reveals that the euroform is better than the veneer board with 21% of total cost in the cost analysis. But this better than that in the side of easiness of construction. In both cases, the buckling of wall panel form and the labor-oriented characteristics of the methods are the future research issues in the rammed earth form system.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2005.11a
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• pp.111-116
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• 2005

The formwork is very important in terms of time and cost of construction project. There have been ample research efforts regarding to technical issues such as types, specifications, and productivities. However, no previous research has addressed managerial requirements of the formwork. Thus, this paper investigated the present status of form work analyzing a case-study company, and derived an improvement plan for the formwork. The findings includes 1) the needs for increasing use of system forms in order to improve the quality and the safety and 2) further development of management system of formwork in order to enhance the efficiency.

• Journal of the Korea Institute of Building Construction
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• v.7 no.4
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• pp.153-159
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• 2007

Recently, as a result of the economic growth, the concentration of population towards the cities and the rise in land prices, the demand for high rise buildings has increased significantly, the trend to build high rise buildings such as the mixed-use development buildings by the domestic construction companies continues. It's very important what kind of form work system is applied on the Core Wall of the high rise buildings to determine the economic efficiency for the whole project. That's because the appropriate selection of the Formwork system enables the construction cost lower, makes the good quality of the finished concrete, reduces the construction period, assurance of safety, and further more, it enables to achieve the successful performance of the projects. Therefore, this research, after comparing the strength and the weakness between the construction methods, focus the point to provide a builder the basic data to choose the right Formwork method.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2006.11a
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• pp.123-126
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• 2006

Existing Deck Plate for a one of system forms, there is various advantage and application actual results increasing rapidly. But design of deck is depending on engineering data collections or design data on deck manufacture ordinarily. When construct, is responsible for deflection occurrence, And Because confirmation of crack occurrence region is impossible, there is difficulty of repair, reinforcement about crack and water leakage. According to got following conclusion as result that economic performance, preservation administration and repair reinforcement develops easy using steel truss snap tie by wedge pin on coating plywood that is slab Panel Wood System Form method of construction there is Deck Plate's advantage. (1) In stab lower part is exposed disjointing in which a criminal is fastened to be interrogated after construction acceptance and repair, reinforcement of crack is possible (2) Construction cost curtailment effect of about 29.2% than conventional type and about 10% than deck plate (3) Construction period reduction of about 3 day than conventional type and about 0.3 day than deck plate (4) Labor curtailment effect more than about $29{\sim}50%$ from conventional type

• Journal of the Korea Institute of Building Construction
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• v.9 no.4
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• pp.111-117
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• 2009

Considering the entire critical path, underground works in construction projects occupy a large part of the total construction period, as well as a large part of the construction costs. Particularly in the downtown area, the scale of underground work has been increasing every year. Currently, underground retaining walls, which are built at construction sites, require many skilled workers, and the works are being undertaken by means of the Euroform+Soldier system, which is quite disadvantageous in terms of the construction period. In order to complement this, forms made of new materials and new construction methods have been developed. Now more than eyer, the shortening of construction periods and the reduction of construction costs is required. Considering this, in this study, the researcher has tried to compare the Euroform+Soldier system, which has been the system most frequently used on construction sites, to the non-supporting form system, which has been used on the sites of civil engineering work. The results of the research revealed that although the Euroform+Soldier system was advantageous from the perspective of material costs, it was disadvantageous in terms of labor costs. It is thought that an additional study on a method for reducing the material costs is required, so as to revitalize the application of non-supporting forms to the construction site.

• Construction Engineering and Management
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• v.17 no.4
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• pp.15-19
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• 2016