• Proceedings of the Korea Concrete Institute Conference
• /
• 2008.11a
• /
• pp.257-260
• /
• 2008

The heat resistance of steel materials tends to weaken due to its high heat transfer properties, which might result in deteriorated strength because of rapidly rising temperature on surface in a fire. Particularly in case of CFT column that bears tensile stress of the structure on its external steel members, a numerical analysis on deterioration of strength and variation of stress shall be first carried out to ensure the structure will have sufficient fire resistance. In the study, based on values obtained from the high temperature material property test of steel materials and concrete, the test to forecast the fire behavior of CFT column was conducted using a finite element analysis method (ABAQUS). An Analysis in a bid to predict the heat transfer and the behavior characteristics by varying the strength of the concrete filled to the range of 40MPA and 50MPA was carried out. As a result of analysis of CFT column on condition of 180-minute exposure under the standard fire condition, 123mm of strain appeared with 40MPA model, while 91mm contraction with 50MPA model.

• Journal of the Korea Concrete Institute
• /
• v.15 no.6
• /
• pp.866-876
• /
• 2003

Experiments were performed for the real sized 12 reinforced concrete columns of 350${\times}$350${\times}$3350 mm with normal concrete in order to observe the fire-damaged behavior of these columns. Columns were heated according to the ISO heating curve. Main experimental parameters were: magnitude of axial load, heating time, cover thickness, and eccentricity. Effects of these parameters on the axial expansion and contraction, rotation, buckling, ISO fire resistance, and structural stability were experimentally quantified. It has been observed that the contraction rate of axial deformation was affected mostly by the duration of heating time and buckling of reinforcement or member by the magnitude of axial load, duration of heating time, cover thickness and eccentricity in order. Based on the experimental observations, ISO fire resistance criteria were qualiatively criticized.

• Journal of the Korean Society of Safety
• /
• v.32 no.2
• /
• pp.72-77
• /
• 2017

In S. Korea, recently, building fire accidents of residential accommodations or recreational facilities have taken place more frequently than before. Among various building constructions, Multi-layered structure, such as office-residential complex, are mostly made in S. korea. $O_2$, $CO_2$, CO, $NO_x$, $SO_x$, and HCl, these gases has toxic hazard and harmful for human body. And it is predicted that different concentration of released gases from diesel pool fire with upper and lower layer. Therefore, this study reports the fire characteristics of Multi-layered structure by analyzing the fire behavior and concentration of combustion gases of a experimental compartment via real scale fire experiment, in order to predict risks and secure safety for similar fire accidents.

• Fire Science and Engineering
• /
• v.21 no.3
• /
• pp.61-68
• /
• 2007

The purpose of this study analyzes heat flows and fire behavior through a reduced-scale model experiments about change of wind velocity in underground life space. When the wind velocity is increased the temperature rise time of the fire room was risen fast. And temperature of fire room was increased. And increase of wind velocity displayed maximum temperature at an opening of the fire room. Heat flows by fire spread increase size of smoke occurrence and flame, and displayed high temperature distribution in passageway than inside of neighborhood department promoting eddy flow spread as wind velocity increases. Finally, heat flows are decided by wind and wind velocity at fire of underground life space, and Wind velocity increases, temperature increase and decrease could confirm that is gone fast.

• Fire Science and Engineering
• /
• v.25 no.6
• /
• pp.156-167
• /
• 2011

The number of buildings is growing at a rapid pace in Korea. It is driven by significant economic improvements, the rapid population growth and urban centralization. Such being this case, some city are underway to building enlargement, Manhattanization. To Solve these problem and ensure the safety of live, fire Evacuation Simulation system is used for safe check of buildings. Forecasting an egress behavior in building fire is so important in order to construct a safe and reliable environment. But, currently most of the fire evacuation simulation system used in practice are foreign software that is not reflect korean conditions. Thus, This study focus on objectives that develop a fire evacuation system considering Korean Characteristics and create 3D space-based topology. so the system calculate evacuation path. This system developed as a result of research can be used by architectural designer in practice due to it is based 3D spatial information modeling.

• International journal of steel structures
• /
• v.18 no.4
• /
• pp.1177-1190
• /
• 2018

This study presents an analytical framework for estimating the thermo-mechanical behavior of a composite beam exposed to fire. The framework involves: a fire simulation from which the evolution of temperature on the structure surface is obtained; data transfer by an interface model, whereby the surface temperature is assigned to the finite element model of the structure for thermo-mechanical analysis; and nonlinear thermo-mechanical analysis for predicting the structural response under high temperatures. We use a plastic-damage model for calculating the response of concrete slabs, and propose a method to determine the stiffness degradation parameter of the plastic-damage model by a nonlinear regression of concrete cylinder test data. To validate simulation results, structural fire experiments have been performed on a real-scale steel-concrete composite beam using the fire load prescribed by ASTM E119 standard fire curve. The calculated evolution of deflection at the center of the beam shows good agreement with experimental results. The local test results as well as the effective plastic strain distribution and section rotation of the composite beam at elevated temperatures are also investigated.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2022.11a
• /
• pp.51-52
• /
• 2022

In previous studies, fire simulation was used to estimate the fire spread path. According to previous studies, the fire spread path was estimated to be the main staircase, but consideration of interior materials and internal bulkheads was insufficient. In this study, the ignition time of the 3rd layer was analyzed using the prediction formula considering the interior materials and internal bulkheads. As a result of referring to the architectural drawings, it was found that the interior material of the 3rd floor was made of polystyrene. The internal ignition time of the third floor using FDTs was calculated to be 14,070 seconds (about 234 minutes). The internal ignition time of the 3rd floor using the Handbook on Design Calculation Methods of Fire Behavior was calculated to be 3,104 seconds (about 51 minutes). As a result of calculating the ignition time through the predictive formula, there is a large difference in the ignition time, so it is necessary to review the condition of the variable as a result of the calculation in the future.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 2008.04a
• /
• pp.11-14
• /
• 2008

This paper is currently being conducted to develop a nonlinear finite element analysis methods for predicting the structural behavior of reinforced concrete structures, exposed to fire. The changes in thermal parameters are discussed from the point of view of changes of structure and chemical composition due to the high temperature exposure. Although, this study considers codes standard fire for reinforced concrete frame, any other time-temperature relationship can be easily incorporated.

• The Transactions of the Korean Institute of Power Electronics
• /
• v.25 no.3
• /
• pp.219-226
• /
• 2020

Given the change in the energy market, large energy storage systems (ESS) is rapidly entering the market. In this rapid spread, fire accidents are becoming an issue. This study attempts to approach the fire from the system point of view to analyze the problems caused by bonding from different perspectives. Moreover, to conduct this study, the fabrication of real objects is dangerous, which needs to be verified through simulation. In this study, we approach the cause of fire that occurs in large-capacity ESS from the system perspective. We focus on determining the effects of cell balancing performed on the BMS after charging. Thus, we analyze the cell balancing behavior and the linkage risks to the various stacks. The study also explores why no fire occurs during 70% operation.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2022.04a
• /
• pp.235-236
• /
• 2022

In the present study, the effect of horizontal vent position on fire phenomena in the enclosure with vertical and horizontal vents was examined using numerical simulation. Case 1 indicates the condition that the horizontal vent is in the center of the ceiling. Case 3 indicates the condition that the horizontal vent is far away from the vertical vent. Case 2 indicates the condition that the horizontal vent is installed between Case 1 and Case 3. The temperature distribution, smoke layer temperature, velocity distribution, and mass flow rate of horizontal vent flow were analyzed. In Case 2, the temperatures were lowest and the mass flow rate through the horizontal vent was largest. This is because the flame is inclined by the inflow through the vertical vent. Hence, to determine the proper horizontal vent location for the high smoke ventilation performance, the inflow through the vertical vent and its effect on flame behavior should be considered.