【 Weak current College 】 on fire safety design of tall building---Power By 【 China power house network 】

Author: Chen Zhi Quan

Along with the social economy development, the building has been around a lot of tall buildings, as the result of a tall building fire, fighting the factors more difficult and therefore should be based on high-rise building oneselk, take the reliable fire protection measures to achieve the purpose of the prevention of fire. Current senior civil building design fire protection standard for tall buildings fire facilities for stringent requirements on the construction of a height exceeding 100M high-rise building, the so-called super high-rise building, in compliance with the General common fire high-rise buildings, increased the reasonable technical requirements of fire safety. Building height of more than 250 civil construction special fire safety requirements to submit national fire departments of the Organization of thematic research and assessments. Super high-rise building fire, fighting more difficult, the serious consequences of the disaster. In Super high-rise building fire at any time during the design process, there will be some new issues. So the correct use of the specification, the use of advanced fire protection technology to ensure the fire safety of super high-rise building is essential. Now some of these issues, for discussion.

I. building facilities security measures

Through qualitative building category, you can fire resistance rating, the fire separation, fire partitions, security, evacuation, fire-fighting facilities put forward different requirements, meet both protection of the fire safety of tall buildings, but also save money. According to the nature of building use, fire hazard, evacuation and rescue of difficulty, a kind of super high-rise building high-rise building, its main parts, the basement level to level of fire resistance, fire resistance rating of the annex shall not be less than level 2.

Explanation: the hotel, Office building, building and other general high-rise public building, should be located refuge layer. Refuge layer is the high-rise building technical school for fire personnel temporary refuge with the floor. Refuge layers can use open, half-open, closed three types. All open refuge layer is not set envelope full open space, usually located in the building top floor or roof. Half-open with height around the refuge layer is not lower than the protective wall, 1.2m top is equipped with a closed window can be opened, natural smoke, prevents smoke. Closed-end asylum with fire-resistant layer of envelope, indoor with emergency lighting, independent air-conditioning and smoke control system for fire doors and Windows, doors and Windows. Set of refuge layer should meet the following requirements:

1. set the number of layers of refuge and two height between layers of refuge, should meet the requirements of the evacuation time, take full account of the construction area, use the function, the number of pedestrian flow velocity and fire spread, from building the first floor to the first refuge layer or two asylum between layers, not more than 15; 2, leads to asylum layer of smoke stairs should be separated by a layer of refuge, with the displacement or lower level broken, but officers must be approved by the upper and lower layers to refuge; 3, taking into account the characteristics of the human body, in the not too crowded, the per capita use area indicators taken refuge layer 0.2m; 4, refuge layer doubles as a device, but the equipment and pipeline to set layout; 5, refuge layer set fire lift exports and other special-purpose telephone, fire off the freight elevator shall refuge layer Office exports.

In addition, you must set the height of the floor for fire personnel temporary refuge room that refuge.

Super high-rise building yishe roof helicopter landing pad. In case of fire, a fire on the top floor with Dodge helicopters evacuated to a safe area, a specific set of technical requirements are:

1. standard layer construction area of more than 1000m; 2, aprons and equipment room, elevator machine room, water tanks, antenna, projection distance should not be less than 5m; 3, export of not less than two, each outlet width not less than 0.9m to protect also has two unit passenger access; 4, set the air barrier around the apron.

High-rise buildings of various vertical tube well are fire spread. In order to prevent fire spread widening, require cable and pipe wells, exhaust system, the exhaust tract, such set up a separate garbage road should not be mixed. At the same time, in order to prevent the fire tube well burnt, expansion of the disaster, all pipes were used fire resistance is not lower than the non-burning material 1.00h production, shaft inspection door with class c fire doors. Various vertical pipeline and cable pull pyrotechnics of mine is, if fire protection processing channels incorrectly, you will not only contribute to the fire, but also as fire and smoke spread, resulting in serious danger of extinguishing difficulties, personal and property safety. Super high-rise building of cable and pipe shaft at each floor slabs with the equivalent of the fire resistance of the body is not burning, the fire separation shall not fill plug all the holes are. Trash often stacked rags, paper scrap wood scrap, such as combustible debris, where cigarette or incinerating waste etc can easily cause a fire. Therefore, the trash is set in the stairway is not safe to rely on external yishe in safety parts, exhaust directly open to the outdoors, set the junk before room, former road, room door should use class c fire door, garbage buckets using noncombustible material manufacture, and be able to close. Buildings used in other similar to refuse delivery of functional and there are combustible materials of shaft, set of fire prevention requirements according to the trash.

Second, fire hydrant system and automatic sprinkler system settings

Fire hydrant system as tall buildings most basic fire-fighting equipment, due to the economic and technical conditions of reason, from savings to investment perspective, there is no alternative to its functionality. Super high-rise building using fire hydrant water 30l/s (residential building for 20l/s). Considering the high rise buildings to oneselk, indoor fire water consumption than outdoor to bigger, indoor hydrant water consumption for 40l/s (residential building for 30l/s), the fire hydrant water 70l/s (residential building for 50l/s), is the specification provided for building fire water limit values. In General, a high-rise building with two and two or more functions. Therefore, the duration of its fire as 3.00h (residential building for 2.00h), taking into account the situation of municipal water supply, which can determine whether to set outdoor fire water tank and its capacity.

Indoor hydrant setting range: 1, high-rise buildings of the subject and podium; 2, the fire service liftFront room or smoke stairway and former Interior, easy to use as soon as possible the firemen to attack a fire hydrant and open up channels; 3, refuge within the protection settings for personnel self-help; 4, roof or a helicopter landing pad, to check pressure and prevent fire hydrant spread to top level and the role of the protection of personnel. 5, indoor hydrant box should fire reel for non-fire professionals the beginning fire fighting.

Indoor hydrant setting technical requirements: 1, fire hydrant enrich the water with hydraulic calculation you want, and not less than 13m to avoid smoke high on fire, and to ensure that firefighters in normal use; 2, fire hydrant spacing in high within not more than 30m, podium within not more than two unit 50m, guarantee full water column at any location within reach-location; section 3, the use of the water supply system, water supply and parallel series two ways, when the fire hydrant for fire protection Design Department of the water pressure is greater than 0.5Mpa, should be set and vacuum unit. As in Super high-rise building fire service does not work, some fire hydrant for fire protection design department hydrostatic pressure is too large, when more than 0 .8mpa, put out the fire in the open water gun produces water hammer effects, easy to make the water supply system of the device is compromised, but the water pressure exceeds 0.5Mpa for fire protection design, so that the water gun produced by reaction, a man difficult to steady operation water gun fire. To this end, to adopt measures specific to decompression set pressure orifice plate or measures such as reducing valve; 4, roof tanks. In order to ensure early fire fire fire-fighting water and water pressure, super high-rise building roof tanks height should meet the most negative point fire hydrant 0.15Mpa hydrostatic pressure. Cannot satisfy, you should set air pressure tank or regulators pumps, turbo-charged facilities. As is the way, its water supply parallel partition fire water tank capacity with high fire water tank of the same capacity, there is a fire, the fire pump supply of fire fighting water should enter high water tank, and in-line water way is allowed; 5, pump adapter. In the fire water supply pressure range of partition is required to set the pump adapter separately. In other words, under existing or will have the ability to fire water supply, determine whether each partition should be located pump adapter. For example, a key to main Jiefang truck, fire-fighting vehicles due to its water supply capacity in 50m around, you can not above 50m located pump adapter; 6, fire fighting pipe network to take measures against overpressure. Commonly used method is to use flow a lift curve gentle fire pumps, safety valve, discharge valve set, avoid pressure caused the destruction of the water supply system.

Automatic sprinkler system settings, in addition to an area of less than 5m ＾ 2 bathrooms, toilets and unsuitable water suppression of parts, other parts need to be set (and the automatic fire alarm system requirements are the same). In response to the fire risk of super high-rise building, evacuation and rescue, and other factors. This setting is necessary.

Third, smoke, particular requirements for electrical connection

High-rise buildings, from toxic flue gas suffocation deaths of staff accounted for 70 percent of the flue gas is the fire of invisible killers. Therefore, to fully consider in building sets the importance of smoke control system. Flue gas flow speed of horizontal 0.3, 0.8m/s, vertical diffusion speed 3.4m/s, when smoke non-stop, you can spread around 1min to dozens-storey building. Flue gas flow speed greatly exceeded the speed of the evacuation. Stairwells, Elevator shafts and the various vertical tube is Highrise vertical spread of important way, easy to form a "chimney" effect. While the staircase and vestibule or combined with front room is the temporary refuge fire, evacuation, fire the elevator and room is firefighters entered the main high-rise building fire. In order to prevent smoke from entering these areas or those parts of the flue gas, ensuring the evacuation and rescue. Therefore, the above parts of super high-rise building set mechanical pressurization system, able to reach the evacuation and rescue channel on smoke-free objectives, from investment and less mechanical smoke extraction system, is feasible. The podium of the stairway to overall consideration. The pressure value should be a smoke staircase 50Pa, former room, combined with front room, closed asylum-25Pa, both convenient for evacuation safety gate open and cannot guarantee the safety of the pressure on the exclusion of flue gas. At the same time, the super high-rise building closed asylum layer set mechanical pressurization facilities, in addition to meet asylum within certain positive pressure values, prevent flue gas intrusion, also to avoid in refuge layer providing breath of fresh air.

Super high-rise building as the level of power supply, emergency lighting load and evacuation signs with special power supply circuit or a battery for emergency power supply, the continuous supply of time of not less than the illuminance for 30min 0.5LX, in addition to the normal set of parts, roof helipad four emergency lighting should be provided. Refuge layer should be set for emergency lighting, the battery should not be less than 1.00h, illuminance should not be lower than 1.00LX, to eliminate the people in the evacuation of frightened, to rescue provides indoor lighting conditions.