• Structural Engineering and Mechanics
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• v.77 no.6
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• pp.819-830
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• 2021

To evaluate the performance of concrete load bearing walls in a structure under horizontal loads after being exposed to real fire, two steps were followed. In the first step, an experimental study was performed on the thermo-mechanical properties of concrete after heating to temperatures of 200-1000℃ with the purpose of determining the residual mechanical properties after cooling. The temperature was increased in line with natural fire curve in an electric furnace. The peak temperature was maintained for a period of 1.5 hour and then allowed to cool gradually in air at room temperature. All specimens were made from calcareous aggregate to be used for determining the residual properties: compressive strength, static and dynamic elasticity modulus by means of UPV test, including the mass loss. The concrete residual compressive strength and elastic modulus values were compared with those calculated from Eurocode and other analytical models from other studies, and were found to be satisfactory. In the second step, experimental analysis results were then implemented into structural numerical analysis to predict the post-fire load-bearing capacity response of the walls under vertical and horizontal loads. The parameters considered in this analysis were the effective height, the thickness of the wall, various support conditions and the residual strength of concrete. The results indicate that fire damage does not significantly affect the lateral capacity and stiffness of reinforced walls for temperature fires up to 400℃.

• Fire Science and Engineering
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• v.21 no.4
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• pp.44-51
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• 2007

Most of the Korea temples of cultural property are wooden buildings and easy combusted. They are often located in mountain area far away from the city. It is very difficult to approach the fight area. The putting out is very difficult in the initial fire time. And for protecting the cultural property in the long-term continuous fire source there are some restrictions in water source and suppression system. In this paper the initial putting out fire due to the forest fire and the protection of cultural property in the long-term continuous fire source were researched. The improved project about fire control facilities of the Korea cultural property was proposed. In the proposed project the facilities using Water mist which can reduce more loss than existing facilities using water are applied. In view of the topographic position the method of eliminating the energy of combustibles and wall for cutting off the heat in the fire control facilities are also mentioned.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.19 no.3
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• pp.235-244
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• 2007

In the case of the fire outburst within a partitioned space, it can disappear inside it through smoldering process if the fire cannot obtain sufficient imflammability. On the contrary, if it obtains it, the fire is not restricted within the room, spreading to the higher levels beyond outside windows and the compartment room. The method to prevent the fire spread through windows is considered to build a balcony or equip with sprinkler facilities. This case study is to identify which effects and controlibility a balcony brings about on the spread of fire through a full scale model experiment. In order to understand the effects of fire spread on the upper levels of the room on fire by changing the length of balcony, the temperature was measured, radiant heat was investigated, and products of combustion were analyzed. The result showed that when fire occured, longer length of the balcony, which linked to the outside wall of the apartments, led to the blocking of the fire spread, lower level of radiant heat, and significantly less transfer of toxic gases, and the driving force of the outburst of flame was identified as the attractive force due to the turbulence of uncombusted gases, which exist on the upper level of the outbursting flame.

• Geomechanics and Engineering
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• v.27 no.6
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• pp.537-550
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• 2021

There are various technical problems need to be solved in the construction process of pre-setting an isolation wall into a double lane in the outburst prone mine. This study presents a methodology that pre-setting an isolation wall into a double lane without a coal pillar. This requires the excavation of two small section roadways to dig a wide section roadway, followed by construction of the separation wall. During this process the connecting lane is reserved. In order to ensure the stability of the separation wall, the required bearing capacity of the isolation wall is 4.66 MN/m and the deformation of the isolation wall is approximately 25 cm. To reduce the difficulty of implementing support the roadway is driven by 5 m/d. After the construction of the separation wall, the left side coal wall is brushed 1.5 m to make the width of the gas roadway reach 2.5 m and the roadway support utilizes anchor rod, ladder beam, anchor cable beam and net configuration. During construction, the concrete pump and removable self-propelled hydraulic wall mold are used to pump and pour the concrete of the isolation wall. In the process of mining, the stress distribution of coal body and isolation wall is detected and measured on site. The results demonstrate that the deformation of the surrounding rock of roadway and separation of roof in the roadway is small. The stress of the bolt and anchor cable is within equipment tolerance validating their selection. The roadway is well supported and the intended goal is achieved. The methodology can be used for reference for similar mine gas control.

• Journal of the Korean Society of Safety
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• v.20 no.4 s.72
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• pp.171-179
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• 2005

It is essential to understand the role of wall lining materials when they are exposed to a fire from an ignition source. Full-scale test methods permit an assessment of the performance of a wall lining material. Fire growth models have been developed due to the costly expense associated with full-scale testing. The models require heat flux maps from the ignition burner flame as input data. Work to date was impeded by a lack of detailed spatial characterization of the heat flux maps due to the use of limited instrumentation. To increase the power of fire modeling, accurate and detailed heat flux maps from the ignition burner are essential. High level spatial resolution for surface temperature can be provided from an infrared camera. The objective of this study was to develop a heat flux mapping procedure for a room test burner flame to a wall configuration with surface temperature information taken from an infrared camera. A prototype experiment was performed using the ISO 9705 test burner to demonstrate the developed heat flux mapping procedure. The results of the experiment allow the heat flux and spatial resolutions of the method to be determined and compared to the methods currently available.

• Fire Science and Engineering
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• v.33 no.1
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• pp.60-68
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• 2019

The paper reports the characteristics of conduction heat transfer to the backside part according to the heating temperature of a composite wall in a lightweight partition used for indoor space compartments. Stud partitions, SGP partitions, sandwich panels, urethane foam panels, and glass wool panels. which are generally used as light-weight partition walls, were selected as experiment samples, and the characteristics of conduction heat transfer to the backside part as the top surface were analyzed by applying heating temperatures of $200^{\circ}C$, $300^{\circ}C$, $400^{\circ}C$, and $500^{\circ}C$ to the bottom surface for 1800 s. According to the experimental results, the maximum backside temperatures at the maximum heating temperature of $500^{\circ}C$ was $51.6^{\circ}C$, $63.6^{\circ}C$, $317.2^{\circ}C$, $124.9^{\circ}C$, and $42.2^{\circ}C$ for the stud partition, SGP partition, sandwich panel, urethane foam panel, and glass wool panel, respectively. The maximum conduction heat- transfer rates at $500^{\circ}C$ were 17.16 W, 18.39 W, 136.65 W, 14.34 W, and 5.57 W for the stud partition, SGP partition, sandwich panel, urethane foam, and glass wool panel, respectively.

• Journal of the Korean Institute of Rural Architecture
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• v.11 no.1
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• pp.25-36
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• 2009

Coastal village and Inland village was village in jeju. This study was cultural elements of stone to village in jeju. Memorial Stone and Stone Monument Street, Shrine, An altar of sarificial site for village tutelary spirits, Bangsatap(pagoda), 25 Bongsu(25 beacon fire stations) and 38 Yeondae(38 signaling sites), Hwanhaejangseong Fortress, Grave wall and Horse pasture walls were included in elements of history and culture to village in jeju. An altar of sarificial rite for village tutelary spirits was generally on the a hill near a village, built of Stone wall. Bangsatap(pagoda) was the kind and the size of stone to a location, that expresses the form and the scale. the form of grave wall was the oval or the rectangle, the latter was frequent. Thatched houses in jeju and facilities in a house, Stone wall, Tongsi(pigsty), Paeng namu and A heights of stone, Spring water and Water collected in a depression, Stone Weir, Horse mill and Dodaebul(Old Lighthouse) were included in elements of life and culture to village in jeju. Stone wall has the multiplicity of the size and the building method in the use, the function and the region. The form of Stone weir was the rectangular figure or the curvilinear figure, the section of that was the right triangle or the rectangular form.

• Journal of the Korean Society of Safety
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• v.38 no.6
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• pp.9-15
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• 2023

Hydrogen is gaining attention as a sustainable and renewable energy source, potentially replacing fossil fuels. Its high diffusivity, wide flammable range, and low ignition energy make it prone to ignition even with minimal friction, potentially leading to fire and explosion risks. Workplaces manage ignition risks by classifying areas with explosive atmospheres. However, the effective installation of a blast wall can significantly limit the spread of hydrogen, thereby enhancing workplace safety. To optimize the wall installation of this barrier, we employed the response surface methodology (RSM), considering variables such as wall distance, height, and width. We performed 17 simulations using the Box-Behnken design, conducted using FLACS software. This process yielded two objective functions: explosion likelihood near the barrier and explosion overpressure affecting the blast wall. We successfully achieved the optimal solution using multi-objective optimization for these two functions. We validated the optimal solution through verification simulations to ensure reliability, maintaining a margin of error of 5%. We anticipated that this method would efficiently determine the most effective installation of a blast wall while enhancing workplace safety.

• Journal of the Society of Disaster Information
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• v.16 no.3
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• pp.421-429
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• 2020

Purpose: The purpose of this study is to present step-by-step countermeasures to prevent fires in sandwich panel warehouses and to enhance on-site fire response capabilities. Method: Interviews of firefighters related to fire sites, advice from fire experts, and experiments on protection performance were conducted to draw up measures for each element to strengthen on-site response capabilities. Result: The fire safety management checklist for warehouse fire safety managers and the installation standards for wall protection of sandwich panel warehouses are presented. In addition, Standard Operational Procedures(SOP) for fire application of sandwich panel warehouses were established for firefighters on-site. Conclusion: Through this study, step-by-step fire safety measures were established for preventing, protecting and suppressing fires in sandwich panel warehouses.

• Journal of the Korean Society of Safety
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• v.27 no.2
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• pp.65-71
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• 2012

Changes in the styles of communities are leading of increases in the number of high-rise apartments and commercial-apartment structures. Tall high-rise structures, while presenting unique economies of scale and cost effectiveness, tend to be highly engineered and complex structures. In the event of a fire, this complexity in design also results in a complexity in the behavior of fire propagation and control. High-rise structures are among the most potentially dangerous due to the high population density in the building, and the inherent limitations on evacuation and on fire control services. One of the most critical points of fire propagation is the movement of fire through the outer wall structures. Controlling such propagation is essential in controlling the spread of the fire throughout the building itself, as well as controlling the potential for its spread to adjacent buildings. In this study, we will be examining the potential for fire control design and effects mitigation using a 1/4.5 scale model. The primary focus of the study will be the effects of extended balconies into the structure of high-rise apartments. The authors will also consider the effectiveness of reduced-scale model tests.