• Proceedings of the Korea Institute of Fire Science and Engineering Conference
• /
• 1997.11a
• /
• pp.353-360
• /
• 1997

The modeling on fire safety assessment for a tall and narrow atrium is carried out using a reduced and full scale atrium models based on the performances of flow behavior in and near comer fire and smoke ventilation system. The comer (or wall) effects on the flame behavior considering air entrainment into a flame was evaluated theoretically and experimentally. Temperature, upward velocity, inlet air velocity, and pressure difference between the atrium space and atmosphere were measured systematically in a reduced scale model. The performance of the modeling to estimate temperature rise and natural air ventilation volume was verified based on the experimental results. Smoke filling rate from a model fire source set at the center of a tall and narrow atrium is fastest in the other cases in which fire source set in or near a corner. This suggested that the centering of the fire source is acceptable as the fire source position to assess the fire safety design for a tall and narrow atrium.

• Journal of the Korea Academia-Industrial cooperation Society
• /
• v.11 no.11
• /
• pp.4671-4676
• /
• 2010

This study is intended to understand flame behavior of the pool fire by height of fire source. Liquid fuels were methanol and n-Heptane which are used in many studies of pool fire. Size of vessel was $100mm{\times}100mm{\times}50mm$ and the vessel was made by stainless steel. Combustion time, mass loss rate, flame temperature, flame height and air entrainment rate from the outside to flame were measured, and flame behavior was visualized with video camera. Based on the experiment, it was found that combustion characteristics of pool fire was decreased according to increase of height of fire source because entrainment volume of relative cold air was increased from the outside to flame.

• Fire Protection Technology
• /
• s.23
• /
• pp.15-19
• /
• 1997

The objective of this paper is to present a equation which can give some insight of the behavior of droplet in a fire plume. The equation is derived with a number of engineering relations drawn from the literature for calculating properties of fire plume. Plume properties considered here include temperatures, velocities and virtual origin. In addition, the drag force for a sphere and the energy equation are considered.

• Steel and Composite Structures
• /
• v.15 no.6
• /
• pp.679-703
• /
• 2013

This paper presents experimental investigations of the fundamental behavior of concrete filled steel tube (CFT) beam-columns under fire loading. A total of thirteen specimens were tested to determine the axial force-moment-curvature-temperature behavior of CFT beam-columns. The experimental approach involved the use of: (a) innovative heating and control equipment to apply thermal loading and (b) digital image correlation with close-range photogrammetry to measure the deformations (e.g., curvature) of the heated region. Each specimen was sequentially subjected to: (i) constant axial loading; (ii) thermal loading in the expected plastic hinge region following the ASTM E119 temperature-time T-t curve; and (iii) monotonically increasing flexural loading. The effects of various parameters on the strength and stiffness of CFT beam-columns were evaluated. The parameters considered were the steel tube width, width-tothickness ratio, concrete strength, maximum surface temperature of the steel tube, and the axial load level on the composite CFT section. The experimental results provide knowledge of the fundamental behavior of composite CFT beam-columns, and can be used to calibrate analytical models or macro finite element models developed for predicting behavior of CFT members and frames under fire loading.

• Proceedings of KOSOMES biannual meeting
• /
• 2006.11a
• /
• pp.283-289
• /
• 2006

This study is a preparation for the application of FSA (Formal Safety Assessment) to the fire safety of ships. FSA is the new-fashioned methodology proposed to prevent ships from the accidents. To make a base of the fire safety assessment about ship's fire protection design and Classification Society rule, statistical informations for the fire safety engineering are investigated. From results, the necessity of new criterion for ship's fire safety design, the need to study the human behavior in the evacuation from fire, and the development of new fire progress model considering special situations in ships are acknowledged.

• Journal of the Korean Society of Safety
• /
• v.19 no.3 s.67
• /
• pp.45-50
• /
• 2004

4-panel of 1m height and 45cm width were fixed on the $40cm{\times}40cm$ bottom plate and the opening of the panel comer was 5cm. Diameter of stainless vessel is loom and its height is 2cm and it located at the center of the bottom plate. 78mL liquid fuel was filled in the vessel and its depth was 1cm. Flame temperature was measured with K type thermocouple, and radiation heat of flame was measured with heat flux meter. Flame height and its behavior was visualized with video camera. and mass burning rate was measured by fuel combustion time. According to the development of fire, flame swirling was begin. From the experiment the mass burning rate was larger and the height of flame was higher than the usual pool fire flame. Flame temperature and heat flux also increased far more than the pool fire. Consequently the swirling air flow through the openings between the panel and thermal buoyance contribute to increase of heat release rate, flame length and mass burning rate.

• Fire Science and Engineering
• /
• v.24 no.4
• /
• pp.33-40
• /
• 2010

A numerical model considering the vapor pressure and the creep models, in the form of a analytical program, for tracing the behavior of high strength concrete (HSC) members exposed to fire is presented. The two stages, i.e., spalling procedure and fire resistance time, associated with the thermal, moisture flow, creep and structural analysis, for the prediction of fire resistance behavior are explained. The use of the analytical program for tracing the response of HSC member from the initial pre-loading stage to collapse, due to fire, is demonstrated. The validity of the numerical model used in this program is established by comparing the predictions from this program with results from others fire resistance tests. The analytical program can be used to predict the fire resistance of HSC members for any value of the significant parameters, such as load, sectional dimensions, member length, and concrete strength.

• Steel and Composite Structures
• /
• v.13 no.6
• /
• pp.521-537
• /
• 2012

In this study, an experimental study is performed to understand the effect of spalling on the structural behavior of fire damaged steel reinforced high strength concrete (SRHSC) columns, and the test results of temperature distributions and the displacements at elevated temperature are analyzed. Toward this goal, three long columns are tested to investigate the effect of various test parameters on structural behavior during the fire, and twelve short columns are tested to investigate residual strength and stiffness after the fire. The test parameters are mixture ratios of polypropylene fiber (0 and 0.1 vol.%), magnitudes of applied loads (concentric loads and eccentric loads), and the time period of exposure to fire (0, 30, 60 and 90 minutes). The experimental results show that there is significant effect of loading on the structural behaviors of columns under fire. The loaded concrete columns result more explosive spalling than the unloaded columns under fire. In particular, eccentrically loaded columns are severely spalled. The temperature distributions of the concrete are not affected by the loading state if there is no spalling. However, the loading state affects the temperature distributions when there is spalling occurred. In addition, it is found that polypropylene fiber prevents spalling of both loaded and unloaded columns under fire. From these experimental findings, an equation of predicting residual load capacity of the fire damaged column is proposed.

• Proceedings of the Korean Institute of Building Construction Conference
• /
• 2021.11a
• /
• pp.242-243
• /
• 2021

The concrete inside the steel tube of CFT columns enables them to have great strength and ductility. CFT columns are also excellent in fire-resistance because explosive heat upon a fire can be contained in the tube by the concrete debris. However, the studies to evaluate the residual strength of CFT columns after a fire have not been conducted enough. The studies to evaluate the residual strength of CFT columns after a fire are indispensable because it is the barometer of the damage of composite columns caused by a fire and the degree of repair and reinforcement work for the columns after a fire. Accordingly, the purpose of this study is to evaluate the deterioration of load capacity and structural behavior of square CFT columns with the same shapes and boundary conditions before and after a fire. The study also evaluates the influential factors of the CFT columns reinforced to secure the residual strength after a fire.

• 한국전산유체공학회:학술대회논문집
• /
• 2008.03b
• /
• pp.415-419
• /
• 2008

In this study, analysis of water mist behavior is performed using numerical simulation. Water mist is characterized by the droplet flow which is one of the multiphase flows and is discrete fluid droplets in continuous air. It is important to choose the proper diameter of droplet-size and the distance between the fire location and the position of water mist because it depends on the buoyancy from fire. Therefore the behavior of water mist with fire should be simulated by FLUENT, a commercial computational fluid dynamics(CFD) program, with Lagrangian discrete phase model. (DPM)