4.

The fire prevention measures of steel structure buildings are divided into active fire prevention and passive fire prevention.

The National Grand Theater successfully applied the fire-resistant steel produced by WISCO, which not only ensured the fire safety, but also realized the architects’ pursuit of beauty…

In other cases, thick, thin or ultra-thin coating can be selected according to the project conditions.

The fire resistance limit of the beam with fire resistance rating of grade 4 can be reached without fire-proof coating.

This method is mainly used in beams, columns and other components with regular shape, pharmaceutical workshops with high requirements for ash falling cleanliness, and low and multi-storey light steel structures.

At present, inorganic fireproof boards are generally used in projects, such as calcium silicate board, gypsum board, vermiculite board, etc.

Cast In Loop

Solid refractories are not only incombustible, but also have large heat capacity.

Fire resistant steel fire resistant steel is made by adding molybdenum and other alloy elements to the structural steel, so that the steel can maintain high strength within the specified fire resistance time.

Using them as a fire-resistant protective layer can slow down the temperature rise of components.

In case of fire, the component will transfer the heat absorbed from the fire to the water in the column, so as to maintain the component temperature at about 100 ℃.

The passive fire protection is mainly introduced.

In engineering application, when the protection time is more than 2 hours, such as steel columns in high-rise buildings, only thick coating type can be selected.

5.

This is the most ideal fire protection method in theory, but it is rarely used in practice because there are few pipe structures and the cost of the circulating system is high, so the problems of rust prevention and antifreeze must be considered.

Active fire prevention mainly refers to the active fire-fighting measures combined with fire detection to change the behavior of the fire scene, such as sprinkler and firefighter’s fire-fighting behavior; Passive fire prevention mainly refers to taking reasonable measures in structural design and structural measures to improve the fire resistance performance of the structure without changing the fire scene.

The shielding method has high cost, takes up a large building space, and is rarely used in engineering due to problems such as fire channeling at joints.

Cladding method fire protection cladding method is mainly to completely wrap the steel structure with solid refractory materials.

In the engineering development and application, it is mainly divided into thick coating fire retardant coating, thin coating fire retardant coating and ultra-thin fire retardant coating according to the coating thickness.

Water filling cooling method: the water filling cooling of fire-proof steel structure is to fill the hollow closed column with water.

2.

According to different methods, the classification of fire retardant coatings is shown in Figure 8 below.

3.

Therefore, if there are no special requirements, it is recommended to select the thick coating type.

The fire-resistant ceiling under the roof can delay the temperature rise of steel roof caused by lower fire.

Spraying fire prevention the so-called spraying method is to apply a layer of fire-proof coating on the surface of the steel structure, so as to form a protective film on the steel structure, and use the fire resistance of the material itself or the dense thermal insulation and thermal insulation protective layer generated by foaming to delay the temperature rise of the steel structure and improve the fire resistance limit of the steel structure components.

The passive fire protection is mainly divided into the following five categories: 1.

Due to different composition materials, thin coated and ultra-thin fire retardant coatings will decompose toxic and harmful gases under fire, causing harm to fire site personnel and firefighters.

Shielding method fire prevention shielding method is usually used for fire prevention of steel roof.

In other cases, fire-proof measures such as fire-proof coating are required, but the thickness of the fire-proof coating can be greatly reduced and the fire-proof cost can be reduced.