【 Weak current College 】 high-rise building on the control of the Fireworks---Power By 【 China power house network 】

Genesis from the high-rise building fire, smoke damage and spread the basic principles, such as on high-rise building fire smoke control method for a review. Large fire accidents showed that smoke is hindering evacuation and fire-fighting operations, resulting in the death of one of the main reasons. In order to minimize the occurrence of high-rise building fire hazards, this article from the Highrise causes smoke harm and spread the basic principles, such as an overview of the high-rise building of several fire smoke control of high-rise building with a view to contributing to the design, construction, fire safety audit management and fire prevention.
Currently, high-rise buildings in the world to flourish, ascendant, has become a symbol of urban modernization degree. As the city of quantity of high-rise buildings, floors increased year by year more and more building, the fire risk of high-rise buildings are more prominent. The high-rise building fire, the smoke is hindering evacuation and fire-fighting operations, resulting in the death of one of the main reasons. Therefore, high-rise building fire smoke control, improve the capacity of the building against fire and security safety has become particularly important.
　　
1 existence of high-rise buildings for fire safety problem analysis
Through nationwide in recent years 86 extremely large fire research, building fire occurrence, development and spread of inducing factor, not only fuel, combustion and to fire three elements of various form factors and conversion factors, but also to the building structure, fire load, fire alarm system, fire fighting equipment, fire, emergency and fire safety quality.
　　
1.1 design deficiencies
　　
A few years ago, some of the fire safety design of tall buildings has been caused by the designers, designers just simply according to the requirements of the architectural layout of the party, the idea to design, did not consider fire safety, and part of the architectural design without fire audit, acceptance is put into use, there are many security problems. While these issues after the form is extremely difficult to be rectified and solid disease, over and over again was the fire department listed as major fire risk, turn over and cannot put things right. Mainly in the following areas:
　　
(1) does not set the automatic fire alarm systems and fire sprinkler system.
　　
(2) interior decoration material does not comply with fire safety standards
　　
(3) fire-resistant design does not meet the requirements.
　　
(4) no smoke control system or the system useless.
　　
1.2 fire audit checks to
　　
Now, the Fire Department in building fire safety audit is still confronted with the "Storm".
　　
1.2.1 "trilateral project"
　　
Construction unit during construction, edge design edge construction, or even arbitrarily change the fire-fighting facilities.
　　
1.2.2 "— handle project"
　　
Top leaders decided to set in stone, what fire separation, fire channel, a setting called "leaders" are invalid under the authority, resulting in the building fire safety hazard.
　　
1.2.3 edge construction edges and applying
　　
Auditing is not passed, the project has been built over, resulting in failure to construction, there are inherent risks, if you want to meet fire safety requirements but to rebuild local knocked.
　　
1.3 construction quality
　　
Many high-rise building construction, fire protection engineering units for his bid is not fire qualification, will host other qualified units, while construction continues as the original class teams, resulting in poor quality construction. Some construction units also implicitly change the drawings, in construction and workmanship affecting building fire performance. Some fire hydrants, fire hoses, fire protection, plumbing, fire doors, fire shutter to poor quality inferior to act as a qualified product, to bring about major fire protection engineering.
　　
1.4 fire management difficult
　　
Modern high-rise buildings in fire-fighting facilities, generally have a tall building fire alarm system, automatic sprinkler systems, automatic smoke control systems, indoor and outdoor hydrant system, fire shutter operating system, there were gas automatic fire extinguishing system, rain or water system, automatic door system. While the current building fire managers work systems still continues the previous security personnel system. Not to mention how to go to scheduled maintenance, inspection and operation of various types of fire-fighting facilities, some managers even fire extinguisher is expired knows nothing of judge.
　　
High-rise building management of another "hidden", is the leading fire safety awareness is weak, the weak performance in single use main building on the better, if two or more units of the total rent a high-rise building, building on their use, causing safety gate closure, the staircases blocked fire problems shirk long drag not resolved.
　　
2 high-rise buildings fires hazards
High-rise building itself has a floor, fuel and electrical equipment, architectural features, the building personnel more features on "more", determines the high-rise building fires, smoke evacuated people died in the fire death more than "three"; the fire smoke toxicity, fire losses large "second"; fire smoke spread, spread fast, "fast"; the building evacuation, fire fighting hard for "difficult" fire characteristics. Therefore, after the fireworks of high-rise building fire control incorrectly may cause serious harm.
　　
2.1 skyscraper fire spread speed
　　
High-rise building in the logging road, such as stairs, Elevator, cable and pipe wells, is not very good control of the spread of fire and smoke can easily form the vertical effects of the "chimney", resulting in the spread of ways and speedFor fast, rapidly spread to higher floors.
　　
2.2 high-rise building fire lasted for a long time
　　
In high-rise buildings, equipment and components, the rapid fire extinguishing and long burn time, produce large amounts of toxic fumes. In a long time under high temperature, reinforced concrete elements and steel structure will vary according to the strength and stiffness of the destruction of a building, a total or partial collapse, causing serious property damage and casualties.
　　
2.3 skyscraper evacuation difficult
　　
High-rise building content that number, the vertical distance, coupled with the fire environment people panic and smoke toxicity, making evacuation became a much more difficult to solve.
　　
2.4 high-rise building fire hazard area
　　
Increasing the size of the modern cities, population, built-up, high-rise building itself spread way more Fireworks. Once the fire, the fire was very easy to spread to the neighboring building, resulting in "burning even camp". 1985 in Harbin, the winter, a high-rise building on fire, that time is in 8-level winds, the fire spread rapidly, affecting 5 Street, hundreds of houses were destroyed.
　　
3 skyscraper fire smoke spread way
Fire smoke carry large amounts of heat can quickly through the various pipe shaft is full of whole building, high temperature smoke permeates, where fuel will cause a fire, to accelerate the spread of fire. Flue gas flow in high-rise buildings, the proliferation of three major ways: fire room a sidewalk a staircase a upper floors a fire in a room outside; exterior; fire room adjacent to the upper room a room.
　　
Fire by a fire room spread out through the direct spread of fuel, heat conduction, convection and heat radiation expand and spread of fire, a lot of examples, the fire spread out from the room are the following ways:
　　
3.1 interior doors
　　
Building room fire, finally spread to the whole building, mostly because the wall Gates failed to put the fire out. Fire door through the corridor within and through the adjacent room open door into the room, and indoor fuel burning. Usually within even if none of the corridor of combustibles, strong heat flow and incomplete combustion products of diffusion, still can spread to distant room.
　　
3.2 wall window
　　
Indoor fire development to complete combustion phase, a large number of high temperature smoke, flame spray out of the window, it will burn out the upper window glass or directly through the open window caused the spread of fire upwards. Exterior window emission of high temperature smoke, flame, in addition to resulting in the spread between the buildings, the high-temperature flame heat radiation also adjacent buildings and other combustible.
　　
3.3 holes on the floor, building of various pipe shaft
　　
Due to the need of building features, there are many buildings in vertical wells road, and opening area, such as stairs and elevator shaft, pipes and cables well, rubbish wells, ventilation and smoke extraction wells road, etc. These shaft pipe and opening area through several floors or even an entire floor in building fires, it will have a chimney effect, causing the fire quickly spread up layers. Experimental measurements, high temperature flue gas vertical wells road up the speed of spread within 3 ~ 5m/s.
　　
3.4 room partition wall
　　
Room partition if combustible materials, or is non-burning, nonflammable materials, if the fire resistance performance difference, so the fire will be subjected to burn through the fire spreading to adjacent rooms.
　　
3.5 across the floor, walls of pipelines and gap
　　
Room fires indoor half is positive pressure state, will force the flame and heat flow through the pipeline by the Chamber floor and walls of any slot holes, the fire spread out. In addition, through the room-temperature metal pipeline in fires, sometimes due to heat conduction heat transfer to the adjacent rooms side, adjacent to the room caused by fire.
　　
3.6 stuffy or Atrium
　　
Because Fireworks is rising up, ceiling-mounted ceiling on the manhole, vents, etc are all pyrotechnics channeling people of holes. Close the top term often do not fire, space very big, very easy to make the fire spread horizontally and, through the holes in the roof close to the surrounded, following the spread of the room and in the spread of the process is not easy to find. Therefore, the stuffy high-rise buildings or the Atrium is the fire smoke spread of important channel vertically.
　　
4 fire smoke control of high-rise building method
On high-rise buildings for fire and smoke control is very complex, on the one hand, to eliminate the buildings in the design, construction, inspection and use the management deficiencies, on the other hand to eliminate and associated persons and people and buildings constitute the system defects.
　　
4.1 building fire safety technology solutions
　　
Realization of the building fire safety, first from technical measures. According to the situation in China, building fire first based on the prevention of early fire, followed by fire control. At this stage, you can use the following security measures:
　　
Set the automatic fire alarm systems, set fire sprinkler systems, internal decoration not ranhua, fire-resistant design, design for smoke control system, design fire stairs, design a tight barrier fire facilities, setting fire elevator and refuge.
　　
4.2 building fire safety management measures
　　
(1) the source of the good design, the architectural design of the qualification certificate, fire zhuanpian, since the Tribunal system.
　　
(2) strict auditing gateway, implement fire safety system, and effectively improve leadership expertise level.
　　
(3) YenCatch the construction management, construction personnel qualification and fire engineering construction supervision system, and strengthen the construction inspection.
　　
(4) the strict management of late, the implementation of building fire facilities detection, signed the transfer and acceptance of construction engineering and fire protection, strengthening of management training and building fire facilities maintenance management.
　　
5 set the smoke control system
Smoke control system settings are adopting certain measures or measures to control the building of the flue gas flow, will fire the smoke in the burning room and fire room where the smoke to be discharged in place, the area to prevent smoke diffusion to evacuation channels and other smoke area, to ensure that evacuation and rescue breathing for stairways and elevator smokeless fire.
　　
5.1 smoke control way
　　
5.1.1 smoke: ranhua smoke, smoke, smoke closed, pressurized smoke.
　　
5.1.2 exhaust method
　　
Natural smoke, smoke, including comprehensive way and negative pressure ventilation exhaust smoke.
　　
5.2 natural smoke
　　
Natural smoke is the role of the natural forces, fire smoke cannot be penetrated to smoke fire stairs and elevator. This way there is no mechanical ventilation, are not affected by power outages, simple, low cost. Although its effects are outdoor wind direction, wind speed, temperature and where the floors of impact is large, but if properly handled, can play a role in smoke. For a large number of high-rise housing, interior decoration is relatively simple, room small, retaining structure fire resistance rating of high buildings, natural smoke means basically to guarantee safety, savings for investment purposes, are also in line with the current reality of high-rise buildings. Common natural smoke control methods include the following:
　　
By exterior construction of full open outdoor smoke staircases, with balcony or concave Gallery as open front room of smoke front staircase, use room ventilation exhaust staircase of smoke, do not rely on the exterior wall of smoke although relying on external staircase or cannot open the window of the front room of natural smoke, smoke extraction shaft is located in General and the shaft had wind.
　　
5.3 mechanical smoke
　　
Is the use of fan for mandatory smoke, it is not affected by the impact of outdoor weather conditions, exhaust gas stabilized effect but requires special ventilation equipment, reliable power accident, auto-control device, and set the specialist maintenance management. Therefore, the cost and maintenance costs are relatively high. But because of the flue duct is effectively a small space, especially when the stairs in front of the room does not rely on the exterior wall or rely on external walls are not turned on, this way are to be adopted.
　　
5.3.1 mechanical smoke extraction
　　
Smoke is considering personnel evacuation zone front room smoke should promptly. Current room at the same time equipped with exhaust system and air supply system, the front room of positive pressure air flow by both, than to guarantee and to adjust the good indoor air before or they will air and exhaust port location setting of the resulting flue gas is not smooth, but difficult to achieve the intended purpose of the exhaust gas.
　　
5.3.2 mechanical pressurization smoke control
　　
Mechanical pressurization smoke control is maintained smoke staircase and vestibule has enough pressure so that the fire caused smoke during cannot access stairs and on the basis of former rooms. Thus, during the fire, into the stairwell and the front room of a certain amount of air, gas excluded staircase and vestibule. This system is relatively simple, but the amount of wind, wind speed calculation must be detailed.
　　
5.4 smoke staircase and vestibule remains positive pressure method
　　
5.4.1 maintain positive pressure areas
　　
From a security perspective, staircase and vestibule are required to maintain positive pressure. But to rely on external walls and Windows of the stairs, when a fire occurred, due to individual Windows open or glass damage, it will be difficult to maintain the required positive pressure values; when the first stairs up to the closure it is difficult to use when pressurized smoke, the two cases should not be taken to maintain positive pressure method.
　　
5.4.2 maintained positive pressure value
　　
Through domestic and international presentations and analyzing it, think in order to prevent flue gas intrusion and fire occurs, women were able to push open the door, stairs should maintain 50pa pressures; front room and fire the elevator room and combined with former room to keep about 25pa pressure more appropriate.
　　
5.4.3 door is opened through the door of the wind speed value
　　
For door is opened through the door of the wind speed value, according to our senior civil architecture design fire protection standard, recommended selection, the value is 0.7 ~ 1.2m/s.
　　
5.4.4 the determination of the total air volume
　　
Positive pressure mode of air should be in accordance with the door closed, keep the given positive pressure values (including through doors and Windows of gap and the amount of air leakage holes) and the door, keeping the door at a given air velocity value calculation of the required air flow, from both a larger value.
　　
5.4.5 air supply system and air ways
　　
Staircase and vestibule, fire the elevator room and combined with former room, positive pressure ventilation system should be separate settings. In order to make the stairs of pressure distribution, starting from the top of every 3-5 layer consists of an air, general use of a typhoon machine through shaft shaft on supply outlet or branch pipe of centralized air methods.
　　
Large fire accidents showed that smoke is hindering evacuation and fire-fighting operations, resulting in the death of one of the main reasons. In order to minimize the occurrence of high-rise building fire hazards, this article from the Highrise Genesis, smoke productionHealth hazards and spread the basic principles, such as an overview of the high-rise building of several fire smoke control of high-rise building with a view to contributing to the design, construction, fire safety audit management and fire prevention.