Basic knowledge of seismic support

The first， What is a seismic support?

Definition: aseismic professional technical facilities closely connected with building structure and with seismic force as the main load. The utility model is composed of an anchor body, a reinforcing suspender, an anti-seismic member and an anti-seismic diagonal brace.

Two, Which systems need seismic support?

According to GB 50981-2014 code for seismic design of building electromechanical engineering, relevant standards and regulations:

1. Domestic water supply system, fire pipeline system, air conditioning and heating system:

Seismic support and hanger design shall be carried out for metal pipes with pipe diameter ≥ DN65.

2. Duct system:

Anti seismic supports and hangers shall be used for smoke prevention air ducts, emergency ventilation air ducts and related equipment, and anti-seismic supports and hangers shall be used for smoke prevention and emergency ventilation ducts regardless of size. (reinforcement)

Air conditioning and ventilation duct: rectangular air duct with cross-sectional area ≥ 0.38 square meters or circular air duct with diameter ≥ 700 is designed as seismic support and hanger.

3. Electrical system:

The electrical pipeline with inner diameter not less than 60m adopts seismic support design

Bridges and bus ducts with gravity not less than 150nm (15kgm) shall be designed with seismic supports.

4. Gas system:

Gas pipelines with inner diameter greater than or equal to 25 mm shall be subject to seismic design.

(in case of conflict with the specification, the specification shall prevail)

Third , What is the material of the seismic support itself? What are the advantages and disadvantages?

Q235B is generally used, including cold galvanizing (electroplating) and hot galvanizing. The thickness of cold galvanized layer is thin, and the thickness of hot-dip galvanized layer is thick. At present, the supports are mostly hot-dip galvanized (the thickness of galvanized layer is generally 70-80) μ m) The accessories are mostly electroplated (the thickness of zinc coating is generally a few) μ m）。 Zinc aluminum magnesium profile has good corrosion resistance, but the price is also expensive.

Four,  How to install seismic support?

The anti-seismic support and hanger system is composed of C-shaped finished channel steel, special anti-seismic connectors, pipe clamps and post expansion anchor bolts of cracked concrete. The size and height of seismic supports and hangers can be adjusted freely through the mechanical connection between seismic connectors and channel steel. The anti-seismic supports and hangers shall not be welded on site, but shall be reliably connected with the original concrete structure with anchor bolts, and the steel structure shall be fixed with prefabricated hole bolts or beam clamps.

Note: the post expansion bolt is a kind of grip, which is said to be more reliable.