• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.48-50
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• 2013

In this study, Car fire for test using ISO 9705 10MW Large Scale Calorimeter. Especially, study on the underground parking for the fire resistance performance. The underground parking lot of the fire resistance regulations in according to with the standard heating curve in Korea. Because of this burning car through experiments to the propose a new heating curve.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2017.05a
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• pp.246-247
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• 2017

In this study, it reviewed the effect of moisture migration in concrete with heating rate on concrete spalling. Concrete specimens with compressive strength 30MPa and 110MPa are used and its size is □100×100×h200mm. And, two kinds of heating rate are set such as IS0 834 and 1℃/min. As a result, in the concrete specimen exposed to ISO 834 standard heating condition, moisture could migrate through pore network and surface concrete pieces fall out by generating moisture clog near the surface in 110MPa concrete specimen. Meanwhile, In the case of concrete specimens exposed to 1℃/min. heating condition, it is appeared that moisture could not migrate because temperature is distributed uniformly. Therefore, surface spalling is not occurred with low heating rate. However, in the case of 110MPa concrete specimen is exploded even though it heated by low heating rate.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.05a
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• pp.91-92
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• 2013

The strength of ultra-high-strength concrete can be reduced even if the spalling is prevented at a high temperature. Therefore, in this study, we measured internal temperature history and residual compressive strength using a 300×300×450mm short column specimens which use the fiber(NY 0.15+PP 0.10+SF 0.30vol·%) and respectively silica sand, washed sand, the slag sand. As a result, the temperature history and residual compressive strength are almost similar regardless of the fine aggregate types.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2015.11a
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• pp.43-44
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• 2015

In this study, spalling property were evaluated from concrete with compressive strengths of 30MPa, 90MPa, 180MPa, applied with fast heating condition(ISO-834 standard heating curve) and slow heatign condition(1℃/min). As a result, the spalling property of concrete was shown differently with compressive and heatign rate. And It could be separated three as non spalling, surface spalling and explosive spalling.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2013.11a
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• pp.50-51
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• 2013

In case of Korea, it goes frequently that underground parks has been burned. Based on standard temperature time curve(ISO-834), gerber, walls, slab of structures are constructed. However, Standard temperature time Curve is not considered that buildings are affected by vehicle fire. that is why it has the hazard that makes building reinforcement feeble. Based on the result that got from vehicle experiment before, we made four RC slab in this experiment and set the fire severity. according to the loading experiment after heating, we measured the effects that makes reinforcement and shape changes. Furthermore, we examined the safty of the structure by comparing before and after heating.

• Fire Science and Engineering
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• v.25 no.5
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• pp.47-53
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• 2011

Fire load in buildings greatly contribute to the time and scale of fire according to the type and quantity of the fire load. Because bookstores have a large quantity of fire load compared with other buildings which may lead to large scale fires, however, their heat release characteristics have been hardly investigated. In this study, to obtain the data applicable for the performance-based fire safety design of bookstores, the specimens representing stacked fire loads were heated in a furnace in compliance with the standard heating curve of ISO834-1:1999 to investigate their heat release characteristics. From the experiment result, the combustion velocity and heat release rate required for performancebased fire safety designs are obtained.

• Steel and Composite Structures
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• v.38 no.2
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• pp.121-139
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• 2021

Ultra-high strength concrete (UHSC) encased steel columns are receiving growing interest in high-rise buildings owing to their economic and architectural advantages. However, UHSC encased steel columns are not covered by the modern fire safety design code. A total of 14 fire tests are conducted on UHSC (120 MPa) encased steel columns under constant axial loads and exposed to ISO-834 standard fire. The effect of load ratio, slenderness, stirrup spacing, cross-section size and concrete cover to core steel on the fire resistance and failure mode of the specimens are investigated. The applicability of the tabulated method in EC4 (EN 1994-1-2-2005) and regression formula in Chinese code (DBJ/T 15-81-2011) to fire resistance of UHSC encased steel columns are checked. Generally, the test results reveal that the vertical displacement-heating time curves can be divided into two phases, i.e. thermal expansion and shortening to failure. It is found that the fire resistance of column specimens increases with the increase of the cross-section size and concrete cover to core steel, but decreases with the increase of the load ratio and slenderness. The EC4 method overestimates the fire resistance up to 186% (220 min), while the Chinese code underestimates it down to 49%. The Chinese code has a better agreement than EC4 with the test results since the former considers the effect of the load ratio, slenderness, cross section size directly in its empirical formula. To estimate the fire resistance precisely can improve the economy of structural fire design of ultra-high strength concrete encased steel columns.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2008.11a
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• pp.484-489
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• 2008

We carried out a one-way heating experiment on the PC panel manufactured by changing the filling depths(20,30,40,50mm) of concrete regarding the fire strength in order to measure the inner concrete pressure which is a direct cause of concrete spalling. This fire experiment was conducted under the fire strength conditions of ISO 834 Standard, Modified Hydrocarbon and the maximum value of Pore Pressure was measured. As a result of analyzing the time it took to reach maximum pressure, it showed that the time rising to the maximum pressure of high strength concrete of 40MPa is slower than that of a 24MPa tunnel lining. In case of ISO fire conditions, spalling damage might take place in heating period of $20{\sim}40$ minutes in the range of $100{\sim}200^{\circ}C$ temperature. In case of MHC fire conditions, the area damaged by fire can appear after a lapse of $25{\sim}50$ minutes in the range of $150{\sim}250^{\circ}C$ temperature.

• Journal of the Korea Concrete Institute
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• v.24 no.5
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• pp.605-612
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• 2012

Spalling of concrete occurs due to vapor pressure ignited explosion, temperature difference across a section, and combination of these factors. Factors affecting spalling can be classified into internal and external factors such as material property and environmental condition, respectively, have to be considered to precisely understand spalling behavior. An external environmental factor such as differences in heating rate cause internal humidity cohesion and different vapor pressure behavior. Therefore, spalling property, vapor pressure and thermal strain property were measured from concrete with compressive strengths of 30 MPa, 50 MPa, 70 MPa, 90 MPa, and 110 MPa, applied with ISO-834 standard heating curve of $1^{\circ}C/min$ heating rate. The experimental results showed that spalling occurred when rapid heating condition was applied. Also, when concrete strength was higher, the more cross section loss from spalling occurred. Also, spalling property is influenced by first pressure cancellation effect of thermal expansion caused by vapor pressure and heating rates.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.30 no.4A
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• pp.391-398
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• 2010

The fire performance of RC slabs with half-depth precast panel after exposure to the ISO-834 fire standard without loading has been experimentally investigated. During heating, according to the ISO 834 fire curve, concrete spalling was observed for concrete without PP(polypropylene) fibers. No spalling occurred when heating concrete containing PP fibers. The maximum temperature of RC slabs with PP fibers with half-depth precast panel was lower than that of concrete without PP fibers. The ultimate load after cooling of the RC slabs that were not loaded during the furnace tests was evaluated by means of 3 points bending tests. The ultimate load of the RC slabs without PP fibers showed a considerable reduction (around 32.5%) of the ultimate load after cooling if compared with of RC slabs with PP fibers. The ultimate load of the RC slabs with half-depth precast panel with PP fibers is higher than that of a full-depth RC slabs with PP fibers. Also, the addition of PP fibers and the use of half-depth precast panel improve fire resistance.