When it comes to curtain walls, I believe everyone can often see them around. It is mainly composed of glass, support system, sealing materials, etc. It is an important part of the building facade and undertakes functions such as heat insulation, sound insulation, waterproofing, windproof, and earthquake resistance. Therefore, the fixation of the curtain wall is very important. If the curtain wall is not firmly fixed, it may cause the curtain wall to fall off, which will pose a certain safety hazard to pedestrians downstairs. In the fixation methods of curtain walls, chemical anchor bolts and mechanical anchor bolts are two commonly used anchoring methods. It is they that endow the building structure of the curtain wall with a modern aesthetic. Then, for the anchoring of curtain walls, should chemical anchor bolts or mechanical anchor bolts be used?
Introduce two kinds of anchor bolts for everyone: chemical anchor bolts. Chemical anchor bolts are divided into ordinary chemical anchor bolts and inverted tapered chemical anchor bolts.
- Ordinary chemical anchor bolt: The chemical anchor bolt is composed of a chemical hose of vinyl resin, a screw, a gasket and a nut.
- Inverted tapered chemical anchor bolt: Commonly known as a set anchor bolt, it is generally used in conjunction with injection-type rebar planting glue. The main components are screws, gaskets, nuts, and rebar planting glue.
Its screw is in an inverted cone shape with 7 sections. Used in conjunction with SHB-rebar planting glue, it is suitable for cracked concrete and non-cracked concrete. It can also be well applied in the anchoring of curtain wall building structures and has excellent properties such as high temperature resistance, aging resistance, acid and alkali resistance, earthquake resistance, and anti-loosening.
Mechanical anchor bolt: It is composed of a propulsion sleeve, a bottom-cut expansion sleeve, an anchor rod, a nut, and a washer. It does not need to rely on any epoxy medium to achieve its anchoring effect and has the properties of high temperature resistance and weldability. The working principle is safe and reliable, that is, the tensile force provided by the anchor to the connected object is provided by the shearing force generated by the mechanical lock key opening and the anchor hole.
Taking Shibang post-bottom-expanded mechanical anchor bolts as an example, it not only passes the 2 million fatigue resistance test and the 120-minute ultimate fire resistance test.
For the two types of anchor bolts, some regions have relevant clear regulations: 1) The selection range of post-installed anchor bolts includes undercut anchor bolts and set inverted tapered chemical anchor bolts, etc.;
2) It is clearly stipulated that ordinary chemical bolts cannot be used;
3) Set inverted tapered chemical anchor bolts need to provide high temperature resistance test reports.
According to the relevant provisions of the standard JGJ102—2003: There are also requirements for construction operations on pre-embedded components on curtain walls. The relevant provisions of clause 5.5 of the standard JGJ102—2003 require:
- The main structure or structural member should be able to bear the load and action transmitted by the curtain wall. The design value of the anchoring bearing capacity of the connector and the main structure should be greater than the design value of the bearing capacity of the connector itself.
- The glass curtain wall column and the main concrete structure should be connected through embedded parts. The embedded parts should be embedded when the main structure concrete is constructed, and the position of the embedded parts is accurate; when there is no condition to use embedded part connectors, reliable measures should be taken and its bearing capacity should be determined through tests.
Anchor bolts for curtain walls
It can be seen from the above regulations that for the anchor bolts used on curtain walls in some areas, mechanical anchor bolts and inverted tapered chemical anchor bolts need to be used. Ordinary chemical anchor bolts cannot be used. And inverted tapered chemical anchor bolts also need to provide corresponding high temperature resistance test reports.
In the installation of curtain wall anchoring, choosing which anchor bolt should be comprehensively considered according to specific engineering needs and construction conditions, and choosing a suitable anchor bolt to ensure the stability and safety of the curtain wall. Small anchor bolts show great effects. In the near future, anchor bolts will play a greater role in building reinforcement projects!
