• Journal of the Architectural Institute of Korea Structure & Construction
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• v.35 no.5
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• pp.133-143
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• 2019

Various problems regarding the wet floor method such as its complicated process and waste of thermal storage have been raised, but the usage of dry floor recommended for long-life housing has declined due to lack of confidence on the performance of dry floor. The purpose of this study is to secure the credibility of dry floor. Under this purpose, this study considered precedent studies and established directions to secure the performance of long-life housing infill, and thus, 9 performance items (Impact sound, Smoothness, thermal comfort, sensation hardness while walking, falling safety, impact resistance, local compression load, local strength and strain at heating) were drawn. In addition, the experiment was carried out for 5 performances except for legal performance, some dry floor performances and whole spatial performance. As a result, an appropriate result from all performances except was obtained. The performance of dry floor was verified for each item from these results and it is expected to use such results as basic data on dry floor in the future.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.12
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• pp.765-771
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• 2019

New Korean-style clay roof tiles have been developed with a focus on significantly reducing the roof's weight while maintaining the strength, absorption rate, and freeze durability. The backflow of rain water through the gaps between roof tiles is prevented by employing baffles and a groove to accelerate water flow. With the new roof tiles, dry construction of a roof is possible without requiring soil. By using the dry construction method with the new roof tiles, a reduction in roof weight of more than 80% is possible compared to the conventional wet construction method with soil. In the case of a traditional Korean-style house with a building area of 99 square meters, the roof weight can be reduced from 135 tons to 24 tons. The new tiles satisfy the KS requirements and are more than 30% lighter than traditional roof tiles. A roof constructed using the new tiles showed no water leaks when exposed to typhoon-class winds with speeds of 17 m/s and 200 mm/h of rainfall, which is 60% higher than the Korea rainfall record. The new roof tiles also have advantages of economic efficiency, workability, maintenance, and aseismicity compared to previous Korean-style roof tiles.

• Tunnel and Underground Space
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• v.4 no.1
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• pp.24-30
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• 1994

Although a dry-system tunnel is not good for reasons fo economy and construction, it has been applied to some tunnels under construction owing to the advantages of good long-term maintenance of tunnel, prevention of consolidation settlement due to the drawdown of groundwater, preservation of the ecosystem, cutailment of operation cost, and so on. The stability of groundwater and the change of the applied water pressure after water proofing were analysed by the finite element method. Using this result, an example of designing the secondary lining for the dry-system tunnel which is to be constructed in low-permeability hard rock was presented.

• Journal of the Korean housing association
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• v.14 no.6
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• pp.135-146
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• 2003

The purpose of this study is to provide the technical methods of apartment remodeling. To gather information, a survey of the technical methods of apartment remodeling in domestic and foreign was conducted. As a case study, three types will be applicable to apartment remodeling： Horizontally expanding remodeling, combining remodeling, conversion remodeling. The results of the study are as follows： 1. Horizontally expanding remodeling type will be applied the dry construction and anchor pile foundation at skeleton and the double flooring at infill. 2. Combining remodeling type will be applied the dry wall construction in order to establish or remove the partition walls. 3. Conversion remodeling type will be applied that converting building equipments and interior finish materials conversion of old to new materials.

• Proceedings of the Korean Geotechical Society Conference
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• 2002.10a
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• pp.411-418
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• 2002

In domestic road construction sites, the compaction control based on strength are widely performed through the direct method with high accuracy, such as Plate Loading Test or Field CBR test. It is impossible to manage all construction sites using the direct method because the direct method requires heavy reaction loads and long measurement time. Therefore, it is necessary to apply the indirect method that could control the relative density of construction sites on the whole. Indirect methods, such as Cone Penetration Test and Fall Cone Test, require extra time for data analyzing and fixed area for test device. In this paper, the field applicability of Soil Impact Hammer (SIH) was investigated comparing with the results of field measurement tests and laboratory compaction tests. SIH developed by Japan Construction Administration and Asanuma Ltd., is a kind of indirect methods for compaction checking. According to the results of SIH performed in domestic road construction site, the subgrade reaction modulus obtained from SIH are similar to that from Plate loading tests in the range of 10 to 40. In comparison with laboratory compaction test, similar compaction line are shown in the dry side of optimum moisture contents.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.721-724
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• 2008

The present study was to develop a dry PFB method similar to the existing gypsum board construction method in order to apply the existing wet PFB method that uses fire.resistant adhesive. It was found that the existing wet method can produce concrete compressive strength of 80MPa and fire resistance of 3 hours with 30mm PF boards. The goal of development in this study was fire resistance of 3 hours through dry construction of 15mm fire resistant boards. The results of fire resistance test showed an increase in thermal durability and thermal strain. It is believed that inorganic fiber reduces thermal strain, and lowers heat insulation performance by 15% or less. This suggests that heat insulation performance was improved by the change in the inner composition of PF board resulting from the adjustment of Al:Si mol ratio, high temperature molding, and dry curing. According to the results of fire resistance test, when the dry PF method was applied, the temperature of the main reinforcing bar was 116$^\circ$C in 15mm, 103.8$^\circ$C in 20mm, and 94$^\circ$C in 25mm, and these results satisfied the current standards for fire resistance control presented by the Ministry of Land, Transport and Maritime Affairs. When a 3 hour fire resistance test was performed and the external properties of the specimen were examined, the outermost gypsum board hardly remained and internal PF board maintained its form without thermal strain.

• Journal of Korean Society of Steel Construction
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• v.29 no.6
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• pp.435-442
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• 2017

A lateral load resisting system is a necessary structural element for the mid- to high-rise modular buildings and concrete cores are known as the most typical lateral load resisting systems in 10- to 20-story modular buildings. It is difficult to construct a concrete core simultaneously with the installation and finishing work of modular units because concrete placed using wet methods might contaminate or destroy the modular unit. Therefore, we have developed a hybrid PC (precast concrete) panel construction method that can construct a concrete core together with the installation of modular units. The hybrid PC panel is a load-bearing element in which a pair of C-shaped beams are combined at the top and bottom of a concrete wall. Concrete cores can be constructed by dry method to connect the hybrid PC panels with bolts. In this study, the details and connection of hybrid PC panels are improved to have the lateral performance comparable to reinforced concrete structural walls and are verified through FE analysis.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.32 no.6D
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• pp.615-622
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• 2012

The aim of shotcrete is to increase the bearing capacity and to protect the excavated surface from erosion by preventing falling of rock mass. Shotcreting method is divided into two types as dry process and wet process. Since 1997, wet process method has been used more frequently than dry process method in field works. The failure to bond, so called rebound, occurs in many case during shotcrete works. The excess amount of rebound has a significant effect on the total construction cost. For example, material and craft-man cost increases, the shooting time delays due to deceleration of work execution stage, work efficiency of craft-man decreases and additional cost to remove the muck generates. In this study, therefore, the experimental analysis of rebound amount and strength was conducted by analyzing the actual construction data for wet process type of shotcreting method upon accelerator contents. Also, the effective and rational method was suggested, which can be actually implemented in the Korea construction sites.

• Journal of the Korean Recycled Construction Resources Institute
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• v.3 no.4
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• pp.313-319
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• 2015

This study relates to an investigation into semi-dry manufacturing process of BP sludge based on non-heating production method. In this study, we conducted a research into reduction of water content ratio which arose from mixture of BP by-products of high water content ratio(50% or higher) with industrial by-products to use such BP by-products as construction materials in large quantity. We measured the reduction rate of water content ratio at the feeding ratio of water content reduction agent(1:0.5) in BP by-products. The results showed that water content ratio was the lowest with 18.5% in the mixture of PA+CFA(1:0.5). Moreover, water content ratio ranged between approximately 9.2% and 11.4% at the age of 1 day to 2 days at the aging temperature of $20-30^{\circ}C$, suggesting that the water content ratio was in the range within 10% which was a level suitable for use as construction material in this study. Meanwhile, we compared and evaluated the physical properties of non-heated BP by-products based on post-aging pulverization method. The results showed that there was no significant difference, depending on pulverization method. When production efficiency and economic feasibility were taken into consideration, it was found desirable to use fine particle pulverizer or pin mill enabling continuous production.

• Proceedings of the Korean Institute Of Construction Engineering and Management
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• 2008.11a
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• pp.800-803
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• 2008

Road is one of the infrastructure facilities, on which lines include various information for guiding a smooth traffic flow. This line marking work is continually removed and re-marked during maintenance. However, some problems exist when the line marking work is conducted. Traditional methods of using grinders and torches have risk of repetitive skill, and workers are exposed directly to the hazardous situations. Moreover, even though the equipment has developed, the line removing work induces environmental contamination and pollution line on the road. Therefore, this study can become one of the eco-friendly cleaning technologies using dry ice blaster equipment, and the new development of equipment will improve method of pavement marking removal. Also, it can introduce innovative automation in construction.