• Fire Science and Engineering
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• v.26 no.2
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• pp.1-10
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• 2012

While a performance based sprinkler design method has been widely used in UK and USA according to fire hazards of occupancies, Korean fire safety industry could not yet accept it due to nonstandardization on risk level of various occupancy. Even only two or three spray pattern sprinkler was produced in Korea fire safety industry, therefore, various spray pattern sprinklers have not yet introduced to major occupancies. Spray pattern sprinklers with one of two K value have been used in all occupancies in Korea Market. UK and USA's Fire industry should produced the spray sprinklers with various K-factors and protection area due to performance based sprinkler design requirement. Therefore the fire load density for main occupancies has been investigated in order to compare with installation standard in advanced countries. Eventually a lot of variations in orifice and K factors of standard heads were set up including special heads needed for high hazard areas such as large drop type, enlarged orifice type and early suppression fast response.

• Fire Science and Engineering
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• v.23 no.1
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• pp.63-69
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• 2009

Article 36 of the Building Code Enforcement Ordinance requires that an exterior evacuation stairs be installed for the buildings of three stories and over with cultural facilities or gathering places which have over $1,000\;m^2$ floor area of public performance halls or recreational facilities. The concentration of population together with the increase of high-rise buildings in cities call for various precautionary measures to be taken against human disasters. For the past ten years high-rise buildings showed 85% of increase, marking a steep rise. This increase of high-rise buildings may lead to human disasters in urban areas and, in case of fire breakout, may cause great loss of human lives and property damages. The most difficult fire-fighting activities in high-rise building fires are those of evacuation. Because smoke spreads through the upper floors, the securement of evacuation route in high-rise buildings may be the only way to minimize loss of lives. In high-rise buildings exterior escape stairs are necessary because it is difficult to secure evacuation route with only direct stairs or interior stairs. The Building Code now in force provides insignificant coverage on the exterior evacuation route installment and therefore becomes an inadequate means for evacuation route securement in high-rise building fires. To compensate for this inadequacy the Building Code should be revised to include a mandatory clause that an exterior evacuation stairs be established for the buildings of ten stories and over which can be categorized into high-rise building group.

• Journal of the Korean Geophysical Society
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• v.6 no.1
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• pp.13-23
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• 2003

Dipole-dipole resistivity and ground penetrating radar(GPR) surveys were performed on an abandoned landfill site filled with asbestos containing material. The main purpose of the study was to estimate spatial extension and volume of the landfill for evaluting the cost for developing appropriate remedial alternatives. Assuming that the bedrock is within 10 m depth, dipole spacings of 2, 2.5 and 5m were set for six survey lines for resistivity measurements. For More detailed information, GPR suvey using 225 Mhz antenna was carried out for twelve survey lines for the shallower information. DC resistivity structures showed few tens ~ hundreds ohm-m for the landfill or alluvial laver, and 1,000~ 5,000 ohm-m for the bedrock. The depth to bedrock is found out to be approximately 5m. GPR survey results represented very clear reflection and/or diffraction events from the boundaries as well as from the blocky construction wastes. With high-resolution GPR survey, depth of the bedrock was resolved up to 2m, which in turn, could be a good indicator for estimating the volume of the landfill. Those depths of bedrock were confirmed by backhoe excavation data for 13 sites. The total area and volume of the landfill were to be approximately 3,953 .$m^2$ and 4,033 $m^3$, respectively.

• Journal of The Korea Institute of Healthcare Architecture
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• v.27 no.3
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• pp.71-78
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• 2021

Purpose: It is important to plan the ward module at a time when the size of beds, the floor area, and the construction budget are all set prior to the hospital design. In this context this study aims (1) to derive various factors affecting the ward module, and (2) to analyze the appropriate room module according to the type. Methods: Design factors related to hospital modules are derived through precedential studies, and the types of ward elevation are classified by reviewing the drawings of 18 case hospitals. And the detailed dimensions and area of the derived elements are analyzed. Results: The X-axis modules of the ward are switched to long span structural columns of 9.9 m, 12.6 m and 13.2 m, but the ward modules still represent 6.6 m. The Y-axis module of the ward shows a dimension of 9 to 9.9m in the process of changing a multi-person room into a four-person room. Type A of curtain wall with columns located on the wall of the room and type B of curtain wall located in the center of the room are analyzed due to their variations. The square window type, which forms the elevation of the square window by exposing the columns to the elevation, and the outframe type, which protrudes from the structural columns and beams, have elevation designs limited. There are, however, no obstacles to the interior space of the hospital room, so the wall composition and furniture arrangement are expected to be free. The ward area of Curtain Wall Type A, which can secure an effective area of 5.9m*5.0m, are 52.1m². The Curtain Wall Type A, Square window type, and the outframe type are 49.8m². Implications: As part of the hospital standard module plan for economical and reasonable hospital building planning, a type was proposed in this study in conjunction with the external design. It is hoped that it be a base for standard module research linked together to the Central Treatment department, Outpatient department and underground parking lot.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.20 no.2
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• pp.763-772
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• 2019

Recently, there is a great expectation for the sustainable effect of TOD and apply it to urban planning and design. However, there are few research on the quantitative evaluation method of the effect. The purpose of this study is to propose a quantitative way to assess the effectiveness of TOD(Transit Oriented Development)'s vehicle traffic reduction in the urban planning phase, based on the land-use plan. Firstly, it proposes a method to convert the information contained in the land-use plan into a network and secondly a method to estimate the travel distance based on the network. In the first phase, the roads in the land-use plan are converted into links and the intersection of the roads into nodes. The area and the height of the zones included in the land-use plan are converted into the weights on adjacent nodes. The second phase assumes the frequency at which travel occurs between nodes on the network is relative to the weights and estimates the travel distance by dividing it into a pedestrian and a vehicle. Then, taking the city without TOD as the object, through comparison present city and alternatively redesigned city to the analysis of TOD effect. In this study, the application of these methods to Bundang as of 1997 and alternatively redesigned Bundang showed that about 39.94 percent of the vehicle traffic reduction effects occurred. Furthermore, the pedestrian traffic ratio of alternatively redesigned Bundang increased to 2.39%.

• Korean Journal of Construction Engineering and Management
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• v.20 no.1
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• pp.52-61
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• 2019

On 30 June, 2017, the Ministry of Land, Infrastructure, and Transport announced the minimum size of parking section will be expanded in parking lots. The expansion of parking section could lead to increase in apartment prices because of increase in total area of the parking lots. It is necessary to adjust the column spacing and number in the parking lots and to apply the 8-Bay long-span parking module with good parking efficiency. According to the study, the construction cost of the 6-Bay module and 8-Bay module was almost the same. But The 8-Bay module was more economical than the 6-Bay module because of the reduction in total area of 8-Bay multi-moduel. The Result of construction cost of 8-Bay modules, Removal Deck-plate RC system was most economical. While the construction cost of PC system was higher due to increase in volume of the member, it would ensure sufficient economy by reducing the girder height to apply a pre-stress method. Also, the construction cost of hollow slab system was the highest. But it could be used as the underground parking lots for apartment, because it had the lowest cost per square meter. This Study has a academic significance by proving the applicability of the 8-Bay Module to underground parking lot of apartment. And it is expected that this study will be used as basic data to derive optimal construction method that applies 8-Bay Module.

• Journal of the Korea institute for structural maintenance and inspection
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• v.23 no.2
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• pp.84-91
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• 2019

Recently, there has been a tendency to improve seismic performance of building structure by installing a steel hysteretic damping device which is economically efficient and easy to install and maintain. However, for a reinforced concrete building, a set of complicated connecting hardware and braces to fix the steel hysteretic damping device yields deteriorated reliability in damping performance. Therefore, this study presents a method of directly embedding a Kagome damper, which was investigated in previous researches, into a concrete structure without additional connecting hardware. Moreover, in this study, a series of experiments conducted to provide a basis of the Kagome damper by confirming the seismic behavior for various embedded lengths. As a result, in a group of the embedded length of $1.0l_d$, the dampers were pulled out, while concrete breakout occurs. In a group of $2.0l_d$, neither pull-out nor concrete breakout occurred, while the dampers show stable behavior. Moreover, the buried length of $2.0l_d$ has 1.3 times better energy dissipation capacity. The system presented in this study can reduce the cost and period for installing, omitting making additional hardware.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.22 no.1
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• pp.719-727
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• 2021

In the field of architecture, retractable devices capable of responding flexibly to the environment have been applied widely to large structures. Among these devices, the aesthetically pleasing retractable membrane is lightweight so that the membrane can be opened easily using only a traction device. On the other hand, because the towed membrane moves as it is connected to the main cable by a trolley, the number of trolleys needed increases in proportion to the roof's area. This study proposes an optimal model for an open-type trolley (OTT), which is used widely in these devices, using topology optimization. The analysis used the ANSYS program. A new model was proposed based on the results and reviewed through the feedback. Through this process, it was possible to develop a prototype with increased durability and reduced weight. For OTT, optimization was performed based on static analysis and the boundary conditions, so three prototypes were designed. A comparison of the proposed trolley with the conventional one under the same conditions revealed an up to 71.04% decrease in volume while the yield-strength reached 8.67 to 11.43%. In conclusion, the optimal trolley proposed was found to be reliable in terms of economy and stability.

• Journal of the Korea Concrete Institute
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• v.22 no.4
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• pp.451-460
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• 2010

There are many types of remodeling, however, engineers and architectures preferred to merge two or more separate units to one very spacious unit. Performing this type of remodeling, in the case of wall dominant apartments, requires partial removal of structural wall causing a concern of structural integrity. However, there are insufficient studies about partial removal, that is, openings. Presently, ACI standard have no clear way to evaluate the effect of opening on the structural wall. AIJ has the provision about strength reduction factor '$\gamma$'. However, this reduction factor cannot exactly evaluate the reduction effect of openings because this factor '$\gamma$' was determined through the elastic analysis. Therefore, in this study, 2 structural wall specimens were tested and many test results from previous studies were collected. Using these data, this study performed statistical analysis about strength of structural wall which have the opening in wall panel. And this study performed parametric study verifying shear strength reducing effect by opening area. In the results of statistical study, previous reduction factor show very conservative results because this equation did not consider other factors, reinforcement ratio and aspect ratio of openings, which was affect the shear strength of shear walls. Therefore we performed parametric study based on the test data and suggest new equation for shear strength reduction factor '$\gamma$'.

• Journal of Korea Water Resources Association
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• v.50 no.6
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• pp.397-405
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• 2017

In case of inundation in a city where populations and properties are highly concentrated, unlike rural areas it is necessary to apply the method of calculating the damage amount considering the sewage overflow and the corresponding building damage. In this study, Dorim 1 drainage sector has been analyzed with Multi-Dimensional Flood Damage Assessment (MD-FDA) for flood forecast. It is analyzed with past flood history through the SWMM model and calculated the amount of damage with district base data and the result of flow analysis. The result of the SWMM model to predict a range of flood, it was shown that the wide area after 4 hours (at 16:30) by sewer overflow. The building damage was estimated using MD-FDA. As a result, the maximum flood area has shown as $205,955m^2$ (0~0.5 m: $205,190m^2$, over 0.5 m: $865m^2$) and estimated building damage of Dorim 1 drainage sector is approximately 15.5 billion KRW (Korean won) and other contents is 7 billion KRW (Korean won). Also from 0 to 0.5 m depth estimated damage is approximately 22.4 billion KRW (Korean won) and over 0.5 m is 100 million KRW (Korean won). Based on the results of this study, it would be necessary to estimate the amount of sub-divided flood damage in urban areas according to various damage patterns such as flood depth and flood time.