• Fire Science and Engineering
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• v.26 no.5
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• pp.92-98
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• 2012

This study analyzed the effect of zoning on the distribution of pressure differentials caused by stack effect and air pressurization in a center core type of 80 story super-tall building. The results showed that maximum pressure difference more than 250 Pa can be generated by stack effect without zoning. Zoning of stairwell only resulted in 10 Pa reduction of maximum pressure difference, however, zoning of both stairwell and EV shaft especially at the same floor revealed 50 % reduction in stack effect. It was also analysed that the minimum required air flow rate occurred when the stairwell temperature reached 50 % of temperature difference between indoor and outdoor.

• Journal of the Korean Society of Hazard Mitigation
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• v.11 no.3
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• pp.83-89
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• 2011

A series of full-scale testing was conducted to examine the effect of stairwell pressurization on the pressure differential between the stairwell and the auxiliary room and between the auxiliary room and the residence. Also, flow velocity profiles at open doors were measured. The building tested was a condominium that had twenty floors above the ground and two floors underground. For pressurization of the stairs, a blower was used to supply air into the stairwell at one location underground. Thirteen different cases were tested, and test variables included the number of floors with open doors and the flow rate of the air supply. When the doors on the first floor were open, the pressure differential between the stairwell and the auxiliary room was distributed almost uniformly except for locations near the first floor. When the flow rate was in the range of 180~270 CMM and the doors of one floor were open, the flow velocity could satisfy the requirement of fire safety standards and the stairwell pressure was positive at all levels. However, the minimum pressure requirement (10 Pa) could not always be satisfied. When doors on two floors were open, the flow velocity requirement could be satisfied by increasing the flow rate, but it was found impractical to satisfy the minimum pressure requirement without causing excessive pressure differential in the area near the blower.

• Fire Science and Engineering
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• v.21 no.3
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• pp.15-23
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• 2007

In the events of a fire in the residential building, highly flammable polyurethane foam sofa produce toxic smokes. In this type of fire, the residents of the building can be gotten into the difficulties of evacuating from the fire places or may be to death due to a lot of hot toxic gases. In this study, CFD simulations were carried out to study the effects of the openings of stairwell on the fire characteristics of fire room and stairwell. Also, analysis of fire hazard based on the tenability limits of fire and FED(fractional effective dose) was performed to evaluate the life safety of the residents of the building. In the fire room, maximum temperature was about $290^{\circ}C$, maximum CO concentration was about 4,740 ppm, and the time to incapacitation of residents in fire room was about t=144 s. In the stairwell, temperature and CO concentration in the condition of openings to be open were even lower than those in it to be closed. Time to the tenability limit with respect to smoke visibility in the stairwell with openings, which was open, was shorter than that of it without openings to be open. It has been shown from this study that opening the stairwell openings is able to decrease the fire hazards to the life safety in the multi-story residential building fire.

• 한국방재학회:학술대회논문집
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• 2007.02a
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• pp.242-245
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• 2007

Stack effects occurred in the stairwell, an important evacuation means of the high-rise building, give a big impact on stairwell pressure difference distribution and it could obstruct evacuation from the building, so should be controlled within proper range. Computer simulation was conducted with CONTAMW2.4 to find the solution of stack effects of the high-rise building. It was able to solve the imbalance pressure difference with a pressurization and a depressurization supplied by fans on higher and lower parts of the stairwell.

• Proceedings of the Korea Institute of Fire Science and Engineering Conference
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• 2010.04a
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• pp.284-288
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• 2010

Length of staircase get longer and evacuation load get heavier in proportion to the building height. Therefore evacuation time could be considered proportional to square of building height. While smoke spreads vertically so rapidly, evacuation speed is too slow, therefore the reasonable measure for the safe of egress route is urgent. Existing pressurizing smoke control system of vertical exit route is seriously limited in function under the stack effect in winter. Stack effect in winter could be overcome with the methods of opening the staircase outward or letting airflow be free between staircase and outside.

• 주택과사람들
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• s.128
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• pp.36-39
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• 2001

• 월간 기계설비
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• s.60
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• pp.80-85
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• 1995

• Journal of the Korea Institute of Building Construction
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• v.14 no.6
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• pp.571-581
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• 2014

In the present study, hollow precast concrete wall (PC Double Wall) for staircase construction was developed. Comparing the conventional walls, the PC Double Wall can be reduced the lift weight using hollow core and improves the integrity between the PC members. The cross-section and re-bar details of the PC Double Wall were developed considering precast concrete manufacturing, constructability, and the structural safety. Particularly, a form system was developed to manufacture thin and hollow core PC wall efficiently. A mock-up test for a staircase using the PC Double wall was performed to verify the constructability and integrity of the PC walls. The test result verified that joint deformation and cracking did not occur as showing good constructability.

• Fire Science and Engineering
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• v.24 no.4
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• pp.109-115
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• 2010

Maximum pressure difference in central core type 80th super_tall buildings was estimated as 75 Pa during no outside wind due to the winter stack effect. Maximum pressure difference of 225 Pa can be obtained depending on the location of air injection fan during the stairway pressurization at fire. Bottom_only air injection system provided the best results in the sense of required air flow rates and pressure distributions. Top_only air supply system was estimated as the worst for this country. It revealed that the decrease of the temperature in the stairway due to the cold outside air injection reduced the required flow rates of the fan and significantly changed the distribution of pressure differences.

• Fire Science and Engineering
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• v.31 no.2
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• pp.24-28
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• 2017

This study compared the performance of a smoke control system in the case of a fire with that in the case of non-fire. Single-pressurization in the vestibule, single-pressurization in the stairwell, simultaneous smoke control of the stairwell and vestibule, which was the pressurization of smoke control, were assessed. The result showed that simultaneous smoke control of the stairwell and vestibule can maintain the differential pressure and is least influenced for the evacuation of evacuees. In addition, for the status of smoke control in Korea and the proper pressurization method, these results highlight the necessity of improving the current pressurization method through the survey.