• KIEAE Journal
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• v.7 no.2
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• pp.39-46
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• 2007

A high-rise building construction in Korea has some problems in engineering, construction and management technologies although the high-rise building construction is recently booming. In addition, the lack of skilled construction labors is increasing, so the development for methods is needed to reduce the labors by prefabrication and mechanization. A re-bar work is one of very important works with regard to cost and schedule management in the high-rise building construction. Nevertheless, the re-bar work has some problems that it is needed many re-bars for joints linking and much time for lifting due to high-rise buildings, and it is difficult to level the skill of labors. So, in this study, the pre-fabrication of three-story height in column re-bars is proposed and the results of an implementation are analyzed and explored by a case study. As the results of case study, the pre-fabrication of three-story heights in column re-bars could reduce the cost in the re-bar work and accelerate the time in the structural frame work. In addition, the pre-fabrication of three-story height in column re-bars could solve the problems such as the waste of many re-bars for joints linking, and the lack of the skilled labors.

• Earthquakes and Structures
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• v.15 no.4
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• pp.395-402
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• 2018

Floor location of adjacent buildings may be different in terms of height elevation, and thus, the slab may hit on the columns of adjacent insufficiently separated buildings during severe ground motions. Such impacts, often referred to as mid-column pounding, can be catastrophic. Substantial pounding damage or even total collapse of structures was often observed in large amount of adjacent low rise buildings. The research on the mid-column pounding between low rise buildings is in urgency need. In present study, the responses of two adjacent low rise buildings with unequal heights and different dynamic properties have been analyzed. Parametric studies have also been conducted to assess the influence of story height difference, gap distance and input direction of ground motion on the effect of structural pounding response. Another emphasis of this study is to analyze the near-fault effect, which is important for the structures located in the near-fault area. The analysis results show that collisions exhibit significant influence on the local shear force response of the column suffering impact. Because of asymmetric configuration of systems, the structural seismic behavior is distinct by varying the incident directions of the ground motions. Results also show that near-fault earthquakes induced ground motions can cause more significant effect on the pounding responses.

• Journal of the Korean Society of Clothing and Textiles
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• v.37 no.1
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• pp.39-50
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• 2013

This study estimates the measurements required to make garments but omitted from Size Korea 2010. Before the estimation of the measurements, the differences of the measurement methods were reviewed through previous research related to clothing construction and various measurement protocols that include previous Size Korea 2010 projects and ISO. The research target was 308 females aged 20 to 30 who lived in Seoul and the surrounding Gyeonggi province. A total of 43 measurements were obtained by the direct measurement method and analyzed in this study. In addition, 17 measurements which differ from the measurement method were also measured directly. These 17 measurements items were waist height, waist back height, waist height natural indentation, body rise, rise length, waist back length 1 & 2, posterior shoulder length 1 & 2, arm length 1 & 2, upper arm circumference 1 & 2, elbow circumference 1 & 2, and waist circumference 1 & 2. To analyze the differences in measurements, the subjects were divided into 2 age groups (20's and 30's). The results were as follows: First, there were big differences in stature, waist height, shoulder length, total length, and neck shoulder point to breast points by age groups; however, there were no differences in 17 measurement (such as shoulder angles) by age groups. Second, it was determined that 'waist circumference 1 & 2', 'waist back length 1 & 2', 'arm length 1 & 2', 'elbow circumference 1 & 2', 'upper arm circumference 1 & 2' and 'body rise & rise length' had significant differences by measurement methods in the entire group as well as each age group. Third, the values of 8 measurements omitted from Size Korea 2010 were estimated using similar measurements. The results of the correlation analysis were utilized to select reasonable independent measurements. Finally, 10 regression equations were obtained by regression analysis; subsequently, these will be useful for estimation of omitted measurements in Size Korea 2010.

• International Journal of Air-Conditioning and Refrigeration
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• v.11 no.4
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• pp.178-187
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• 2003

In this study, ventilation flow rate and pressure rise through a tunnel are simulated numerically using computational fluid dynamics (CFD) for various conditions such as roughness height of the surface of tunnel, swirl angle and hub/tip ratio of jet fan, and entrance and exit effects. By using a modified wall function, friction factor can be predicted with respect to the Moody chart within 10% of error for the circular pipe flow and 15% for the present tunnel. For more accurate design, the effect of the swirl angle and hub/tip ratio of jet fan, which is not included in the theoretical equation of pressure rise by jet fan needs to be considered.

• Journal of Korean Society on Water Environment
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• v.27 no.1
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• pp.115-119
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• 2011

The mobility of groundwater in the soil environment has an important role in the soil environment and absorption of plant. Therefore, studies on the mobility of groundwater considering the physical and chemical properties of soil is very important. In this study, movement of water due to change in soil particle size were observed by capillary rise. The height of the capillaries was measured according to capillary diameter, temperature and solution concentration. The inner diameter of each capillary itself is 0.012, 0.016, 0.024, 0.027 cm, and experiments were performed at $22^{\circ}C$. As a result, the height of the capillaries decreased with increasing capillary diameter, and the solution temperature but increased with increasing concentration. Changes in the height of the capillaries are interpreted to related with surface tension by the Young-Laplace equation. Also on the mobility of groundwater, the increase of water and soil temperatures can be significant factors caused by ion strength and global warming as well as pores in the soil particles. The results of this study is considered to provide the basic data on the behavior of groundwater in the soil environment.

• Earthquakes and Structures
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• v.6 no.4
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• pp.437-455
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• 2014

Some conventional lateral load patterns for pushover analysis, and proposing a new accurate pattern was investigated in present research. The new proposed load pattern has load distribution according weight and stiffness variation in height and mode shape of structure. The assessment of pushover application with mentioned pattern in X type braced steel frames and steel moment resisting frames, with stiffness and mass variation in height, was studied completely and the obtained results were compared with nonlinear dynamic analysis method (including time history analysis). The methods were compared from standpoints of some basic parameters such as displacement, drift and shape of lateral load pattern. It is concluded that proposed load pattern results are closer to nonlinear dynamic analysis (NDA) compared to other pushover load patterns especially in tall and medium-rise buildings having different stiffness and mass during the height.

• Journal of the Korean housing association
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• v.16 no.2
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• pp.75-82
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• 2005

The High-rise Residential Buildings are recently consuming a lot of energy because of the vertical height rise in case of supplying cold and hot water. It is required to a appropriate solution in occurring discomfortable use and unexpected conditions of High-rise Residential Buildings on account of the difference of water supply pressure on top and bottom floor, faucet outlet pressure rise. Thus, the purpose of this study is to research on practical use status of Cold and Hot Water Supply System through Question Survey in High-rise Residential Buildings and to analyze problems.

• Earthquakes and Structures
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• v.19 no.3
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• pp.175-188
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• 2020

The Hengda Group super high-rise building in Jinan City uses the frame-core tube structural system. With a height of 238.3 m, it is above the B-level height limit of 150 m for buildings within 7-magnitude seismic fortification zones. Therefore, it is necessary to apply performance-based seismic design to this super high-rise building. In this study, response spectrum analysis and comparative analysis of the structure are conducted using two software applications. Moreover, elastic time-history analysis, seismic analysis under an intermediate earthquake, and elastic-plastic time-history analysis under rare earthquakes are performed. Based on the analysis results, corresponding strengthening measures are implemented at weaker structural locations, such as corners, wall ends connected to framed girders, and coupling beams connected to framed girders. The failure mode and failure zone of major stress components of the structure under rare earthquakes are analysed. The conclusions to this research demonstrate that weaker locations and important parts of the structure satisfy the requirements for elastic-plastic deformation in the event of rare earthquakes.

• International Journal of High-Rise Buildings
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• v.1 no.4
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• pp.271-281
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• 2012

Tianjin Goldin Finance 117 tower has an architectural height of 597 m, total of 117 stories, and the coronation of having the highest structural roof of all the buildings under construction in China. Structural height-width ratio is approximately 9.5, exceeding the existing regulation code significantly. In order to satisfy earthquake and wind-resisting requirements, a structure consisting of a perimeter frame composed of mega composite columns, mega braces and transfer trusses and reinforced concrete core containing composite steel plate wall is adopted. Complemented by some of the new requirements from the latest Chinese building seismic design codes, design of the super high-rise building in high-intensity seismic area exhibits a number of new features and solutions to professional requirements in response spectrum selection, overall stiffness control, material and component type selection, seismic performance based design, mega-column design, anti-collapse and stability analysis as well as elastic-plastic time-history analysis. Furthermore, under the prerequisite of economic viability and a series of technical requirements prescribed by the expert review panel for high-rise buildings exceeding code limits, the design manages to overcome various structural challenges and realizes the intentions of the architect and the client.

• Journal of the Korean Professional Engineers Association
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• v.38 no.1
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• pp.52-54
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• 2005

Korean metropolises are choked by lack of green space to attain the limit of horizontal expansion. The alternative plan is trying total expansion that the green zone and road are made from the rest site by high-rise buildings. And high-rise building can solve indiscriminate development to attain the limit situation. The building of landmark can be the image of the nation and the pride of the citizen. The relaxing the height restriction of government can be whole nation's interests. Appearing high-rise building in overpopulated city is the subject of a generation and this trend cannot be avoided.