【 Weak current College 】 City Centre commercial space features and design of fire

Summary: this article provides an analysis of large and medium cities underground commercial fire characteristics, fire design on your own understanding.
　　
Keywords: fire safety design of fire prevention measures fire partitions secure channel
　　
In recent years, in order to ease the city of contradictions, the largest city centre districts began a massive urban development, including improvement of transportation and expansion of the commercial capacity of the urban center to three-dimensional direction, business start and underground space.
　　
Underground commercial space in addition to any other own advantages, from fire prevention and safety, there are many more worthy of our attention. Because of its main commercial space is located underground, so make it fire prevention aspects must be very cautious.
　　
Underground space although for external natural or man-made disasters typically have strong protection capability, if internal disaster, than on the ground to be dangerous. In particular, where a large number of people belonging to the activities of commercial space, if there is no security protection in the event of fire, in a big way.
　　
Underground fire prevention features of the environment
　　
Underground commercial space of the internal fire and ground building fire in basically the same principle, but cannot fail to note some of the features of the underground environment so that the problem of internal fire protection of underground space is more complex, more difficult. If you prevent improperly, the hazards are more serious. Fire protection of underground space has the following characteristics:
　　
The largest underground environment characterized by sealing, generally only by a small number of entry and to contact the external space, for evacuation and fire rescue brings many difficulties. First of all, in a closed room space easy to make people lose their sense of direction, especially for those substantial access to underground space but on the internal layout of the situation is not very familiar with, in this case there is a fire, psychological horror and action on clutter than serious ground building, interior space, the larger, more complex layout, the greater the danger. Second, in a closed space, maintain good air quality is not as simple as there is much more difficult to form space, into the exhaust can only be achieved through a small amount of air, in the mechanical ventilation system failure, we must rely on natural ventilation of remedies. In addition, the closed environment so that the material is not easy to fully burn, in the event of a fire the smoke after combustibles are substantial for smoke control, and exclude the more complex, for internal personnel and external personnel evacuated into disaster relief are negative.
　　
Another characteristic of underground environment are in the following city high-rise, people from indoor to outdoor walking directions and surface buildings on the contrary, this makes from underground space to Earth open space of evacuation and shelter have a vertical uplink, downlink consumes physical strength than to affect the speed. At the same time, the bottom-up evacuation route and internal flue and the flow of hot air, to the personnel of the evacuation. Additionally, for attached to surface building underground commercial space, and is connected to ground, commercial buildings and in space, internal disaster spread from the bottom up and extended in may, for the upper part of the building a great threat.
　　
For underground commercial space for special environmental conditions at the time of the fire protection design, starting with aim and prevention, not to the disaster occurred. Followed by the disaster and disaster for effective control. According to the General requirements for fire protection of ground and underground environment features, a large underground commercial space of fire should do the following: to prevent the occurrence of fire; the fire, police and alerts; ensure that all staff in the spread of fire and smoke flow diffusion before orderly evacuation, withdrawal of underground space; the fastest fight fire, put the material losses reduced to a minimum.
　　
To meet these requirements, mainly from two facets: the layout of the building for the prevention and suppression of fires on the conditions, another is to establish a good fire prevention and fire suppression systems, equipped with advanced equipment.
　　
Internal control: disaster early
　　
1) should limit public spaces in underground tanks for flammable and smoke large quantity of the goods, the prohibition of the use of flammable decoration material, the main structural fire resistance rating for the level, the repair material should be 1 hour fire resistance in noncombustible materials as above, and to a lesser extent on the use of commercial space, open fires and non-smoking. Underground shopping street of shops in the centrally arranged canyinlei and unified management to control easy gas, and can form a distinctive flavor food Street. In addition to combining customer rest facilities designated smoking Department, otherwise the absolute prohibition of smoking.
　　
2) on the one hand to improve perception of the degree of automation equipment and agility to keep in good condition, on the other hand also need to set manually monitoring system. If the key parts of CCTV camera. In addition to large underground shopping street, full-time firefighters 24-hour patrol, ensure timely detection of validation of the disaster, disaster, through cable system alerts, and various disaster response directive.
　　
Control of the disaster's second measures, once the fire, as far as possible, the spread of the fire of the partition and the spread of smoke flow, including fire, smoke partition partition, smoke and fire stairs hanging wall, etc.

From the architectural point of view of the fire on the layout design:
　　
Graphic layout and the spatial organization: building layout, concise, uniform plane as structured to avoid too many twists and turns, fixed line clear; internal space should remain intact, reducing unnecessary change and high base much, people in one easy to familiarize yourself with the environment in order to avoid hazards due to lost and increase the sense of panic. Transverse longitudinal corridors and therefore even channel comparison rules should be composed of grid channel system, channel end obvious location settings secure export, reducing lost and can't find export possibilities. Underground commercial space from nature, roughly divided into circulation space, business services, space, space, and other parts of the rest. These space organization mayTo have a diverse, but all should follow the changes in the consolidated view in principle, not only from the perspective of architectural art level is needed, and fire safety requirements also is consistent, and fire prevention features most closely is the common space and rest space, they are often grouped together, on fire is also very favourable. For example, in the main channel of the intersection layout beautification and rest facilities, Office space, compared to the spacious to fire evacuation, if more than one channel to a natural lighting outdoor underground Plaza, Plaza can not only play the role of the passenger terminal, you can also play the role of refuge boot than effective artificial guide.
　　
Fire District:
　　
Larger underground public space should be fire-resistant walls, fire shutter and fire door for fire compartmentation, automatic sprinkler system installed so that the fire under control, to a lesser extent and fight, in this sense, the commercial street-layout more open lobby more favourable, such partitions easier.
　　
Smoke partition:
　　
General area smaller than the fire prevention Division, and not cross fire partitions, set the vertical wall, reference smoke Japan underground fire experience, underground channel, set the spacing between the vertical wall of smoke is less than 40 metres, 0.5-0.8 m high, so that the smoke flow subject to numerous obstacles. This smoke vertical wall, you can also set binding ceilings, a fire at a controlled fall, usually hidden in the ceiling.
　　
Security number and location of exports:
　　
On the concentration of the underground fire safety requirements of commercial space, there are two control indicator, a unit of area is fire, another is required from any point in a building to the nearest safe export distance not exceeding 30 m, requires every 60 m is going to be a gateway to the export of ground, in order to meet a timely evacuation of the entry you want to bring a sufficient number and arrangement of uniform, each entrances serve area comparable to prevent partial entrance flow too centralized, blocked. The width of the entrance to the service area of maximum flow density suited to ensure the safety of passengers in the allowed time passed, for every fire unit, safe export cannot be less than two, and to directly out to the outdoor ground, when the densely populated or larger, you should also increase the amount of the security for export.
　　
Channel:
　　
From fire prevention perspective, the requirements of the channel should meet the two requirements, a system simple to minimize the possibility of people get lost, another is to have the maximum width of the pedestrian to adapt in order to ensure the rapid adoption of capacity, to prevent jams.
　　
Smoke stairs:
　　
Sets the smoke is isolated from the fire stairs and smoke spread along the vertical direction, the policy measures can reference ground experience and specifications, standards and a corresponding increase in exports for personnel safety, his former room area should be greater than the ground floor of building, it is recommended that before room for 10-15 square meters, so the firefighters and evacuate personnel flow lines cross contradiction to relaxation. And strengthen the role of temporary refuge. Two security entrances of distance shall be not less than 60 m, end strip channel should be controlled at 15 meters, the floor more underground commercial space also wish to set up a front room protection fire lift.
　　
In addition to architectural layout for the creation of wide open evacuation of evacuation conditions, you also need some guidance measures, at the junction, stairs, etc., are required to have a marked position of plane diagram and from that point to the nearest safe entrance signage, as well as the obvious "security entrance" flag. Emergency lighting in addition to protecting power, you should use the penetrating smoke ability strong light source, should have the perfect disaster prevention Center and broadcasting system, the alert is issued, through radio-guided groups orderly evacuation, for emotional stability and it is also necessary.
　　
In sum, the underground commercial space design and on the ground of fire protection of commercial space design has a lot of fire similarities, but also have specific aspects. Modern commercial space in the most seeking business interests at the same time, more and more attention to the publicity, the creation of comfortable environments, especially in the beginning the most unique cultural tastes, embodying the essence of the commercial space, pay close attention to the customer's psychology and behavior, which is the underground floor of commercial space of common parts. Therefore, the ultimate purpose of underground commercial space is to create humanized space, meet customer demands for comfort, the underground floor of commercial space, its reasonable fire design is indispensable to this goal.