• Korean Journal of Construction Engineering and Management
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• v.17 no.5
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• pp.3-12
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• 2016

Recently government is set to expand its policy to promote technical proposal tendering in a dimension of technical competitiveness reinforcement. Because a variety of complicated techniques are applied in technical proposal tendering and variables could be occurred in terms of cost, schedule, constructability and others when techniques are reflected on design document collaboration management among participants is considered insignificantly. So the research would determine primary management factors and presents management direction for collaboration among participants. First action for this is categorization of hindrance factors to collaboration into five factors as 'Poor work processing', 'Communication cap among participants', 'Lack of understanding about technical proposal tendering', 'Difficulty of decision making' and 'Insufficiency in managing the work data'. Second correlation analysis is conducted between the categorized factors and participants according to tasks in technical proposal tendering to figure out the correlation degree of variables. If there is a strong correlation between variables, hindrance factor in that case regarded primary management factor to collaboration and finally management direction is presented at each task.

• Journal of the Korea Institute of Building Construction
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• v.22 no.6
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• pp.565-575
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• 2022

Thanks to the latest developments in digital architectural technologies, free-form designs that maximize the creativity of architects have rapidly increased. However, there are a lot of difficulties in forming various free-form curved surfaces. In panelizing to produce free forms, the methods of mesh, developable surface, tessellation and subdivision are applied. The process of applying such panelizing methods when producing free-form panels is complex, time-consuming and requires a vast amount of manpower when extracting production data. Therefore, algorithms are needed to quickly and systematically extract production data that are needed for panel production after a free-form building is designed. In this respect, the purpose of this study is to propose mathematical algorithms for the automatic generation of production data of free-form panels in consideration of the building model, performance of production equipment and pattern information. To accomplish this, mathematical algorithms were suggested upon panelizing, and production data for a CNC machine were extracted by mapping as free-form curved surfaces. The study's findings may contribute to improved productivity and reduced cost by realizing the automatic generation of data for production of free-form concrete panels.

• Steel and Composite Structures
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• v.43 no.3
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• pp.389-401
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• 2022

This study investigated the flowability and mechanical properties of cost-effective steel fiber reinforced ultra-high performance concrete (UHPC) by using locally available materials for field-cast application. To examine the effect of mixture constituents, five mixtures with different fractions of silica fume, silica powder, ground granulated blast furnace slag (GGBS), silica sand, and crushed natural sand were proportionally prepared. Comprehensive experiments for different mixture designs were conducted to evaluate the fresh- and hardened-state properties of self-consolidating UHPC. The results showed that the proposed UHPC had similar mechanical properties compared with conventional UHPC while the flow retention over time was enhanced so that the field-cast application seemed appropriately cost-effective. The self-consolidating UHPC with high flowability and low viscosity takes less total mixing time than conventional UHPC up to 6.7 times. The X-ray computed tomographic imaging was performed to investigate the steel fiber distribution inside the UHPC by visualizing the spatial distribution of steel fibers well. Finally, the tensile stress-strain curve for the proposed UHPC was proposed for the implementation to the structural analysis and design.

• Fire Science and Engineering
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• v.30 no.5
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• pp.54-59
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• 2016

Steel is a structural material that is inherently noncombustible. On the other hand, it has high thermal conductivity and the strength and stiffness of the material are reduced significantly when exposed to fire or high temperatures. Because the yield strength and modulus of elasticity of steel are reduced by 70% at $350^{\circ}C$ and less than 50% at $600^{\circ}C$, the load-carrying capacity of steel structure at high temperature rapidly lose. To be accepted as a fire-resisting construction, the fire test should be performed at the certificate authority. On the other hand, the fire test on a full-scale structure is limited by time, space, and high-cost. The analytical method was verified by a comparison with the fire test of H-section columns under compression and thermal analysis based on a finite element method using the ABAQUS program, and the numerical analysis method reported in this study was suggested as a complement of an actual fire test.

• Journal of The Korea Institute of Healthcare Architecture
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• v.3 no.4
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• pp.17-26
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• 1997

The construction of the health care facilities in terms of medical institutional source cost much and affect on management of another sources like staffs for the health care delivery systems and the medical service. For it is hard to change the physical component of the facilities, the reasonability and the efficiency of the facilities should be the major considering point. Consequently, the purpose of this study is to represent the basic data for determining the size and type of corridor space in ward by investigating the design pattern of existing facilities and analyzing several model according to corridor type.

• Journal of the Korean Solar Energy Society
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• v.26 no.4
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• pp.9-16
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• 2006

Geothermal-energy has been getting popular as a natural energy source for green buildings these days. Public building with gross area more than $3000m^2$, planned after March, 2005, should spend about 5% of total building cost for equipment run by natural energy source (e.g. geothermal, solar heat, solar power, etc) according to renewable energy promotion law in Korea. As a result geothermal-energy using heat pump system is emerging as a effective alternative for realistic and economic plan although design guidelines and construction code for the system is in progress and technical data is far from sufficient. The quantitative analysis on the performance of geothermal-energy using heat pump system is insufficient for appropriate design of it. In this paper, cooling performance of geothermal-energy using heat pump system of residential and retail etc. mixed-use building has been analyzed on the basis of temperature comparison between inlet and outlet of heat exchangers of the operating system. Additionally, dry-bulb temperature and relative humidity have been measured and analyzed together as an index of indoor thermal environment.

• Journal of the Korean Society for Advanced Composite Structures
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• v.6 no.4
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• pp.51-57
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• 2015

Various hybrid dampers have been developed in Korea to control the vibration due to a wind and earthquake. In order to minimize the installment space, cost and construction process, the new hybrid friction damper is developed. This hybrid damper is composed of several rotary friction components having two frictional joint. Because of these components, the building vibration due to wind and earthquake can be mitigated by hybrid friction damper. In this paper, various dependency tests were carried out to evaluate on the structural performance of two joint rotational friction component of the hybrid damper. Test results show that two joint rotational components do not depend on a displacement and a frequency of forcing but friction coefficients is reducing as a clamping force is increasing.

• International Journal of High-Rise Buildings
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• v.5 no.4
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• pp.271-291
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• 2016

There is much architectural and engineering literature which discusses the virtues of exterior bracing and diagrid systems in regards to sustainability - two systems which generally reduce building materials, enhance structural performance, and decrease overall construction cost. By surveying past, present as well as possible future towers, this paper examines another attribute of these structural systems - the blend of structural functionality and aesthetics. Given the external nature of these structural systems, diagrids and exterior bracings can visually communicate the inherent structural logic of a building while also serving as a medium for artistic effect. Viewed in this light, the visual appeal of these systems can be enhanced to give a tower a more distinct urban identity. This entails the creation of structural elements that are aesthetically pleasing, geometrically coherent and that demonstrate dexterity of application in regards to a building's composition, while also respecting the laws of physics and mechanics. In this fashion, an artistic approach can exhibit structural systems as not just purely rational features that enable the construction of tall buildings, but as important visual components that afford opportunities for creative expression. This paper, therefore, synthesizes the concepts of structural performance and creative artistry to facilitate a better understanding of the aesthetic developments in skyscrapers worldwide.

• Journal of the Korean housing association
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• v.25 no.3
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• pp.53-62
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• 2014

This paper investigates whether the use of Rainwater Harvesting Systems (RWHSs) to provide water for washing machines in Hong Kong residential buildings would be financially attractive. In such systems, rainwater is accumulated and reused for doing laundry, garden irrigation, flushing toilets, and even drinking. Thus, the analysis of RWHSs' financial feasibility is essential for construction projects. RainCycle is used to validate financial feasibility, considering particular circumstances and data relevant to the Hong Kong context. A range of different scenarios by adjusting three factors are evaluated: catchment area, water demand, and discount rate. It is suggested that $2,000m^2$ would be a suitable catchment area in a typical Hong Kong residential building and it is demonstrated how water demand and discount rate influence the financial performance of RWHSs. In particular, the financial performance of RWHSs is sensitive to discount rates. The results suggest that the RWH system would be worthwhile for buildings with a lower number of floors, but would barely achieve financial validation in Hong Kong's super high-rise residential buildings.

• Journal of the Korea Institute of Building Construction
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• v.20 no.6
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• pp.567-576
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• 2020

This study proposes additional items to be recognized as defects in a defect lawsuit through a case analysis of lawsuit cases in apartment housing. Identifying these defects prevents an unexpected increase in litigation costs, delays in the date of litigation, and emotion repercussions or additional lawsuits. In this study, the defects that were not discovered by the existing occupants and construction companies, but were newly discovered in litigation, were defined as defects in lawsuits. Fifteen cases of lawsuits were analyzed and a total of 77 defects were derived. Each item was then reviewed for location, work type, number of occurrences, and cost. The results were yielded 23 defect items, which were validated by appraisers who directly appraised the cases. In addition, the derived defect factors were analyzed. Finally, the 23 defect items were categorized into 10 main factors which include attributes such as causes of occurrence and characteristics. This can provide an overall area of defects to be considered in addition to existing defect items in the life cycle of the housing. The results of this study can contribute to reducing the actual occurrence of defects and minimizing the disputes in the case of defect lawsuits.