• KSCE Journal of Civil and Environmental Engineering Research
• /
• v.34 no.1
• /
• pp.95-105
• /
• 2014

Reinforced concrete (RC) shield tunnel lining must be designed for fireproof performance because the lining is sometimes exposed to very high temperature due to traffic accidents. Both experimental and numerical studies are carried out to evaluate fire resistance performance of precast RC tunnel lining systems. In the experimental studies, six full-scale precast RC tunnel segments are exposed to fire in order to examine the influence of various parameters on the fire resistance performance of precast RC tunnel lining. We used the temperature curve of the RABT criteria, which are severe conditions of fire temperatures. The fire test showed that the explosive spalling was not observed by substituting concrete to PP fiber reinforced concrete. A transient heat flow analysis was carried out in consideration of the material properties that change with temperature, and the results showed good agreement with the test results.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.7 no.4
• /
• pp.323-333
• /
• 2005

Recently the fire is happening at the tunnel and underground - structure internationally. We are socially the economy the actual circumstances which serious loss is happening due to an fire occurrence when fire happened which is closed like tunnel and underground - structure, the collapse from the burglar degradation of strength of tunnel concrete lining and human life damage happen. It causes big problem while the long time disconnects a traffic network. While the fire happened in this research at the tunnel, the paper construct a basis data to deduce the specification regulation about stability of tunnel concrete lining. In this paper, the experiment was carried out for the prevention of explosive spalling of tunnel to use a reinforced Polypropylene concrete which mixes a Polypropylene which are known for the thing by being efficient at a protect of explosive spalling of the concrete. According to the firproof test result of reinforced Polypropylene admixture mortar, Polypropylene admixture of prevention of explosive spalling analyzed 0.2%-0.25%.

• Journal of Korean Tunnelling and Underground Space Association
• /
• v.20 no.2
• /
• pp.331-346
• /
• 2018

In the tunnel of domestic high - speed railway, the main fire - fighting facility, fire - extinguishing passageway, is installed. However, due to the high pressure of the high - speed train, frequent breakage and maintenance are caused by strong shock and long - term vibration. In order to solve these problems, it is necessary to improve the fire door, but in Korea, it is installed by submitting a certificate by simple KS F 2296 performance test. At present, it is developed as a simple test certification by producing a real scale fireproof door without the theoretical examination in advance, so that a high cost for improvement is occurring in Korea. Therefore, through this study, structural analysis study which can preliminary structure review was carried out in order to design the refuge connection passage fire door and to improve the performance improvement. In order to secure the reliability of the result value, the official authentication test (KS F 2296) were compared.

• Fire Science and Engineering
• /
• v.26 no.6
• /
• pp.45-50
• /
• 2012

The spalling causes the sever reduction of the cross sectional area with the exposure of the reinforcing steel, which originates a problem in the structural behaviour. By coating surface of high strength concrete with fireproof mortar, the high strength concrete is protected from the spalling in fire and the method to constrain the temperature increase of steel bar within the concrete. The purpose of this study is to investigate the temperature history properties of lightweight mortar using perlite and polypropylene fiber for fire protection covering material. For this purpose, selected test variables were the contents and length of polypropylene fiber. As a result of this study, it has been found that addition of polypropylene fiber to mortar modifies its pore structure and this causes the internal temperature to rise. And it has been found that a new lightweight mortar can be used in the fire protection covering material.

• Proceedings of the Korea Concrete Institute Conference
• /
• 2008.11a
• /
• pp.689-692
• /
• 2008

HSC(High Strength Concrete) have superior properties well as improvement in durability compared with normal strength concrete. In spite of durability of HSC, explosive spalling of concrete is serious problem in structure safety. Therefore, Solving methods are required to control the explosive spalling. The properties of concrete are affected by changes of temperatures. Compressive strength and elasticity modulus were degraded depending on a rise of temperatures. Also, change in microstructure and dehydration of concrete subjected to high temperatures. This paper is concerned with change in microstructure and dehydration of the alumino silicate fire protection materials at high temperatures. The testing methods of fire protection materials in high temperature properties are make use of SEM, TG-DSC and XRD. From the experimental test results, influence of high temperatures on microstructure of alumino-silicate fire protection material was identified, including chemical dehydration of C-S-H and CH. The chemical dehydration of CH under various temperatures from to 450 to 600$^{\circ}$C has been measured using the TG-DSC. However, developed alumino silicate fire protection materials showed good stability in high Temperatures. Thus, the results indicate that it is possible to fireproof panels, fire protection of materials.

• Fire Science and Engineering
• /
• v.25 no.3
• /
• pp.91-98
• /
• 2011

This study is about fire resistance performance of wood framed lightweight wall including a middle lintel as a traditional wall form in Korea. The target wall is non-loadbearing system which constructed with $38{\times}89$ mm ($2"{\times}4"$) wood frame and fireproof gypsum board covering, including a middle lintel made of $150{\times}150$ mm section glue-laminated timber. As a test results, all specimens have showed fire resistant performance over 90 minutes and tests were maintained until flame occuring on Specimen-l, 2, 3 at 91 min, 97 min and 98 min respectively. Fire resistance of the heat side gypsum board was 45 minutes and charring rate of middle lintel was equivalant with that of usual timber. The wood stud inside wall system showed relatively quick combution characteristic when exposed to high temperature with no temperature rising delaying time caused by moisture evaporation because of the dehydration preceded during the early period of fire side gypsum board resist to heat.

• Journal of the Korea institute for structural maintenance and inspection
• /
• v.22 no.5
• /
• pp.72-81
• /
• 2018

Fireproof structures using concrete, built-up panels and dry walls are usually used in walls inside fire compartments. However, demand for glass walls is emerging due to increase in interest in visibility and external appearance. In this study on steel fire resistance walls using insulation glass, fire resistance tests and performance evaluations were conducted on 60 minute fire resistance walls and exterior walls which could be applied to interior fire compartments and 90 minute fire resistance walls which could be applied to curtain walls. According to the tests, the specimens satisfied the required fire resistance performance. The finite element analysis was conducted after the tests to evaluate the fire resistance performance of the glass walls. The analysis results showed that the preliminary evaluation of fire resistance performance would be feasible.

• Fire Science and Engineering
• /
• v.30 no.5
• /
• pp.36-45
• /
• 2016

Integral fire shutters are installed indiscriminately, regardless of evacuation. There is always the risk of an accident because integral shutters are applied mainly to corridors, passages, and stairs of schools This study evaluated the problem of integral shutter's entrance, evacuation, construction management, and maintenance control through a fire shutter accident case, including present condition of fire shutter installed at school of Okgil, Bucheon and Dongtan, Hwaseong. The results suggest that emergency lighting or signs for passage be set up to check location of entrance easily and install obstruction sensors at fire shutter to reduce life damage. In addition, the number of efficiency tests of fire shutters should be increased by running a trial test monthly or weekly to maintain the performance of fire shutter. Schools need to install a fire shutter- applied sprinkler at the entire floor.

• Journal of the Korea Institute of Building Construction
• /
• v.18 no.6
• /
• pp.569-576
• /
• 2018

In modern society, a huge number of the buildings have been constructed with RC structure. RC structures have many structural instabilities due to earthquake, typhoon, construction fault, design phase errors. Therefore, many reinforcement methods are being implemented to solve this problem. In the reinforcement method, the organic epoxy adhesive used in the FRP reinforcing method is abruptly damaged when exposed to high temperature, which is directly connected to the fall of the reinforcing material. Therefore, the present study was conducted to develop inorganic refractory mortar with a certain level of adhesion ability to reduce the heat transferred to FRP reinforcement when exposed to high temperatures. As a result of the test, it showed high adhesion strength at room temperature condition with the inclusion of EVA resin, and showed no performance deterioration up to about $300^{\circ}C$ even under heating conditions. Also, it was confirmed that the backside temperature was lower as the thickness increased, and converged to a constant temperature of about $780^{\circ}C$ after 2 hours of heating.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
• /
• v.12 no.2
• /
• pp.99-107
• /
• 1998

This dissertationhas confirmed the non-flam mability of cast mold transformer that is increasingly used lately. As a research progress, the investigation has been performed on the installation status and each line of the subway system which have the most mold transformer accidents, and the impediment status of the transformer for rectifier and the high-voltage distribution transformer per each manufacturer. Then, a high voltage mold of the actual mold transformer has been installed in the horiwntal heating furnace and the heat has been applied by the standard heating temperature curve of KSF 2257(Fireproof testing meth od of the construction structures: 1993). Accordingly, the combustibility of the mold transformer based on the test results has been found that 78 minutes has been required for the complete burning per the KSF 2257 combustion test curve and that, after stopping the heat application of the horizontal furnace after ignition, the flame progress has not been made but shown as the self-extinguishing characteristics when the flame progress has been checked. Thus, the non-flammability and self-extinguishability of the mold transformer have been confirmed. The result of this dissertation has indicated that the accident involving mold transformer has been progressed and expanded by the dielectric breakdown or void due to the crack in the mold rather than a fire accident caused by a short-circuit or an overload.r an overload.