According to China's national standard "Building Design Fire Code", the fire resistance level of buildings is divided into four levels. The fire resistance level of a building is determined by the burning performance and fire resistance limit of the building components (beams, columns, floor slabs, walls, etc.). Generally speaking:
First-class fire-resistant grade building is a reinforced concrete structure or a mixed structure composed of brick walls and reinforced concrete structure;
Second-class fire-resistant grade building is a mixed structure composed of steel roof frames, reinforced concrete columns, or brick walls;
Third-class fire-resistant grade building is a brick and wood structure composed of wood roofs and brick walls;
Fourth-class fire-resistant grade is a combustible structure consisting of a wood roof and refractory walls.
On determining the fire resistance level and durability of a building:
For a newly designed house, the level should be determined according to its functional requirements - including the height and area of the building, the degree of impact on life and property and politics, and according to the requirements of the level, such as the design requirements of staircases and elevators, combustion performance and fire resistance limit of the components, structural and fire resistance limit of the building, the fire resistance level and fire resistance limit of the building. Combustion performance and fire resistance limit, structural seismic requirements, etc. to design.
On the completed or old building, it should be the main components of the performance of the judgment, against the corresponding specification requirements to determine.
Extended information
1, a fire-resistant building: the main building components are all non-combustible.
2, the second level of fire-resistant buildings: the main building components in addition to the ceiling is incombustible, the other is non-combustible.
3, the third level of fire-resistant buildings: roof load-bearing components for combustibility.
4, four fire-resistant buildings: firewalls are non-combustible, the rest are refractory and combustible.
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