Potential Hazards Of Membrane Structures

- Sep 21, 2017-

The special architectural form of membrane structure engineering is analyzed and the corresponding fire prevention measures are put forward to ensure the fire safety of this type of building.
Membrane structure is close to a period of time to obtain rapid development of a new type of space structure, it because only sustain tension, makes material mechanical performance into full play, and with light weight, allowing across large space and design into various shapes, short construction period, easy maintenance, low cost, can satisfy the use requirement of many sided, the advantages of easy to blend with natural environment, the international architectural building known as the 21st century.
Membrane structure is a new form of architectural structure. It USES the fine fabric as material, and USES the flexible wire rope or rigid support structure to transfer the membrane surface by bending the inner surface force. In this way, a structure system with a certain stiffness and tension can cover a large span of space. The development of membrane structure was mainly dominated by inflating structure, but after the appearance of tension membrane structure, the inflatable membrane structure was replaced by the tensioning membrane structure except for the special domain.
Can see membrane structure architecture in today's world in the form of large space building has become a mainstream, but as a new type of architectural form, membrane structure can say there are many in the field of fire safety with the current spec, meaning that it there is a great deal of conflict with the traditional concept of building fire protection, for example, building materials fire endurance of zoning, fire prevention, safety evacuation of personnel, the application of automatic fire alarm system, and the application of fire extinguishing system are traditional architectural design mode cannot meet the.
Used for high strength and flexibility of the film called film membrane structure material, it is the most important part of the membrane structure engineering, and steel, concrete, lightweight plank is equal, in the containment of membrane structure architecture is both the function of building materials, materials and structural system of the tensioning force.
There are clear rules for the combustion performance and fire resistance of buildings in the building design fire protection code and the fire protection design code of high-rise buildings. Currently, there are two kinds of film materials used in membrane structure building. The type of membrane is made of fiberglass fabric and coated with polytetrafluoroethylene (PTFE), which can achieve A grade A. The other class is based on nylon fabric, coated with PVC and other resin materials, and the combustion level can reach level B1. If the former should be able to meet the requirements, but if the latter is used, the fire resistance of the whole film structure building is determined to be further analyzed.
Membrane structure is mostly used in the gym, theatre, exhibition building's audience hall, exhibition hall, the area, length, can according to need to be sure, the architectural space span is big, difficult to divide the fire zone, fire cases form fire spread easily, but if used for commercial, schools, canteens, vegetable markets, such as construction, will be restricted by the specification, must make fire partition, but most of the building height and large span, divided into fire partition are difficult, therefore, in the event of fire, all kinds of fire bucket pull effect on the vertical channel. When the flue gas is below the membrane surface, the top airflow level moves horizontally, causing the fire to expand laterally, and it is easy to form a widespread fire spread.
The structure of the membrane structure is huge because of the space, the person inside the film space to reach the outside outlet distance long, so the evacuation time is long. The smoke rose and spread horizontally, blocking the view of the evacuees and increasing the difficulty of evacuation. In addition, there are many people in the large space, and the evacuation is easy to be delayed.
Membrane structure architecture space is generally higher, the span is larger, after a fire smoke spread, detector and slower to action than in ordinary buildings, and we usually use the automatic sprinkler system in the building layout is more difficult, more can't effectively play a role of fire. This kind of large space building fire can meet many difficulties. For example, the heat radiation is strong, the smoke is thick, the fire spread fast, the way is much. In addition, in the face of the new membrane architecture, we lack this kind of large space building fire of actual combat experience, the attack to the ascent of fire extinguishing homework, reconnaissance, fire water supply to a lot of difficulties.