Building curtain walls are divided into glass curtain wall, metal curtain wall and stone curtain wall according to different panel materials. No matter what kind of curtain wall, the connection between the load-bearing structure system and the main structure of the building is usually through embedded parts or post-anchoring Achieved. In addition to the self-weight load, the curtain wall also bears the influence of wind, earthquake and other loads. Therefore, whether the connection between the embedded parts and the main structure of the building is reliable and durable is directly related to the structural safety and service life of the curtain wall.

  (1) The relevant requirements of Article 5.5 of Standard JGJ102-2003:

  1. The main structure or structural member should be able to withstand the loads and effects transmitted by the curtain wall. The design value of the anchor bearing capacity of the connector and the main structure should be greater than the design value of the bearing capacity of the connector itself;

  2. The pillars of the glass curtain wall and the main concrete structure should be connected by embedded parts. The embedded parts should be buried during the concrete construction of the main structure, and the position of the embedded parts is accurate; Measures and determine its carrying capacity through tests.

  3. Forced embedded parts composed of anchor plates and symmetrically arranged anchor bars can be designed in accordance with the provisions of Appendix C of this code.

  4.The embedded steel plates and other connection measures of the grooved embedded parts shall be designed in accordance with the relevant provisions of the current national standard "Code for Design of Steel Structures" GB 50017, and their bearing capacity shall be determined through tests.

  5.When the glass curtain wall frame and the main structure are connected with anchor bolts, they shall meet the following requirements:

  (1)The product should have a certificate of conformity; (there is a test report of the chemical composition and mechanical properties of the steel, with design method information and ex-factory certificate).

  (2)Carbon steel anchors need to be treated for corrosion;

  (3)After the bolt is added, the single pull test and the node (group) pull test must be performed on site. The load applied in the test should be 1.5 times the load design value without obvious slippage. If necessary, the limit pull test should be carried out in the testing unit .

  (4)There should be no less than two bolts after each connection point, the bolt spacing and the distance from the bolt to the edge of the component should not be less than 70mm, and should be designed as a node where the bolt is sheared;

  (5)Bolt diameter should be determined by bearing capacity calculation and should not be less than l0mm;

  (6)It is not appropriate to perform welding operations on the connectors that are in contact with the chemical anchor;

  (7)The design value of the anchor bearing capacity shall not be greater than 50% of its ultimate bearing capacity.

  6.When the curtain wall is connected with the masonry structure, it is advisable to add reinforced concrete or steel structure beams and columns to the main structure of the connection part. The strength level of the connected main structure concrete should not be lower than C30. Curtain walls should not be connected to masonry masonry, nor to light walls.

  (二)Construction requirements for rear anchors

  Back anchors are widely used in the construction of building curtain walls. Especially in the reconstruction and expansion of old buildings, a large number of curtain wall projects, or even all use back anchors. A large number, or even all, of back anchors are used in the curtain wall project, and the construction quality is not well controlled, which will bring hidden safety risks to the use of the curtain wall

。

  For the construction requirements of the rear anchors, there are clear regulations in the specification "Technical Specification for Anchorage of Concrete Structures" JGJ 145-2004.

  1. Rear anchors include expansion bolts, reaming bolts, chemical planting reinforcement and other types of bolts.

  When using the rear anchor, in addition to considering the performance differences of various bolts, factors such as the properties of the base material, the mechanical properties of the anchor connection, the type of the connected structure, and Hu Wu's seismic fortification requirements are also considered.

  Expansion bolts and reaming bolts shall not be used for tension and edge shear (effective anchorage depth of 10hcf margin for margins), tensile and shear composite structural members and non-structural members of lifeline engineering. (The non-structural components of the building include: external walls, partition walls, curtain walls, suspended ceilings, billboards, etc.).

  Chemical planting bars and screw rods, which meet the anchoring depth, can be applied to the back anchoring of structural members and non-structural members with tensile strength, edge shear, tensile shear composite stress of seismic fortification strength not greater than 8 connection.

  2. Pay attention to the construction quality of anchor bolts. For the construction of anchor bolts, the standard "Technical Specification for Anchorage Behind Concrete Structures" JGJ 145-2004 provides:

  (1) Drilling requirements for anchor bolts:

  A. When drilling, the main stress-reinforcing bars should be avoided, and the waste holes should be filled with chemical anchor glue or high-strength resin cement mortar;

  B. After drilling, use a compressor or a manual air cylinder to remove the dust and debris in the hole, then wipe the hole with acetone, and keep the hole dry.