Why do wires of civil air defense projects pass through welded steel pipes?

Article 7.4.3 of "Design Code of civil air defence basement" stipulates that the wires for civil air defense projects shall be welded steel pipes.

According to civil air defence basement Design Code:

The air defense basement has the requirements of "anti-nuclear, anti-conventional, anti-chemical and biological weapons", and the treatment of electrical pipelines entering and leaving the air defense basement must be consistent with the engineering protection and sealing functions. The protection and sealing of these parts are very important. Poor sealing of the pipeline will cause air leakage and poison leakage, and even the indoor pressure will not exceed the pressure during filtration and ventilation.

The embedded pipeline on the protective airtight partition wall should take corresponding protective airtight measures according to different engineering resistance levels. The embedded pipes on the sealing wall shall be sealed.

Galvanized steel pipes with a wall thickness of not less than 2.5 mm shall be selected for the electrical embedded pipes passing through the external wall, airport wall, protective airtight partition wall and airtight partition wall. Pipes in other parts can be selected according to the design specifications or regulations of relevant ground buildings.

Note: Civil air defense projects are underground protective buildings built separately for the protection of personnel and materials, civil air defense command and medical rescue in wartime, and basements built in combination with ground buildings that can be used for air defense in wartime. ? The civil air defense project is an important facility to guard against the enemy's sudden attack, effectively cover people and materials, and preserve the war potential.

Extended data

Calculation of area

Calculation of building area, effective area and shelter area of air defense basement.

The building area of air defense basement mentioned here refers to the enclosed space area surrounded by the components that directly bear the impact fluctuation load, that is, the enclosed space area formed by the external wall, adjacent wall, door frame wall, sealing wall and protective partition wall of air defense basement.

Air defense underground outdoor passages, shafts, stairs, air ducts, etc. Can not be included in the construction area of air defense basement. The effective area of civil air defense refers to the area that meets the use of personnel and equipment, and the value is the difference between the basement construction area and the structural area. Civil air defense shelter area refers to the effective area of civil air defense for sheltering personnel, materials and vehicles. Its value is the effective area of civil air defense minus the area of the following parts:

(1) area of oral cavity, anti-virus channel and closed channel;

(2) the area of professional equipment such as ventilation, water supply and drainage, power supply, chemical defense and communication;

(3) the area of toilets, washrooms and boiling water rooms.

Baidu Encyclopedia-Code for Design of Civil Air Defense Basement

Baidu encyclopedia-civil air defense basement

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