Views: 0 Author: Site Editor Publish Time: 2024-03-16 Origin: Site
In the design and construction of embedded parts, the following types are often applied: embedded anchor bar, embedded anchor bolt and chemical bolt. So, what are their differences?
The embedded anchor bars shall be HRB400 or HPB300 reinforcement. Straight anchor bars and anchor plate shall be welded in T shape. Pressure submerged arc welding should be used when the anchor bar diameter is not more than 20mm, and punched plug welding should be used when the anchor bar diameter is greater than 20mm.
The diameter of the stressed straight anchor bars of the embedded parts should not be less than 8mm, and should not be greater than 25mm. The number of straight anchor bars should not be less than 4, and should not be more than 4 rows. The anchor length of the straight anchor bar is determined, the anchor length of the shear and compressed straight anchor bar should not be less than 15d, d is the diameter of the anchor bar.
When the anchor bar uses HPB300 grade reinforcement, the end should also have a curved hook.
Q235B shall be used or Q355B, and the diameter shall not be less than 20mm. Anchor bolt should be set up with curved hook, or anchor plate, or anchor beam, and its anchorage length should not be less than 25d.
The anchor bolt should not be used to withstand the horizontal reaction force at the bottom of the column. This horizontal reaction force is first transmitted to the concrete foundation through the friction force between the column foot plate and the concrete surface; when the horizontal force at the bottom of the column is greater than the friction force, shear bonds need to be set to shear resistance.
After the installation and correction, the anchor cushion plate (the thickness should be 0.5~0.7 times of the bottom plate thickness) and the bottom plate should be welded firmly. The bolts shall be fastened with double nuts, and the nuts and bolt pads shall be spot welded.
Chemical bolt grade is generally 4.8 (market standard), 5.8 (national standard), 8.8 (high strength), composed of screw, nut, gasket and chemical pipe.
The chemical pipe of the chemical anchor bolt is composed of vinyl resin, quartz sand particles and curing agent. Through the synthetic resin mortar bonding the screw forms the adhesion between the screw and the hole wall, and forms the whole with the anchored object, so as to achieve the role of fixing the member and improving the bearing capacity of the component.
Embedded anchor rod | Anchor bolt | Chemical bolt | |
Steel Grade | HRB400 | Q355B | 5.8S |
Diameter(mm) | 24 | 24 | 24 |
Area(mm2) | 452.2 | 452.2 | 452.2 |
Section Effective Area(mm2) | 452.2 | 352.5 | 352.5 |
T ensile ultimate stress (N/mm2) | 540 | 470 | 500 |
T ensile yield strength (N/mm2) | 400 | 355 | 400 |
T ensile strength design value (N/mm2) | 300 | 180 | 240 |
Anti-tensile bearing capacity design value(KN) | 81.4 | 63.5 | 84.6 |