What standard should be adopted for the specification of steel structure anchor bolts?

1, steel structure anchor bolt specification Q235

2. Anchor bolts can be divided into fixed anchor bolts, movable anchor bolts, anchor bolts and bonded anchor bolts. According to different shapes, it can be divided into L-shaped embedded bolts, 9-shaped embedded bolts, U-shaped embedded bolts, welded embedded bolts and floor embedded bolts.

3. It consists of Q+ number+quality grade symbol+deoxygenation method symbol. Its steel grade is preceded by "Q", which represents the yield point of steel, and the number behind it represents the yield point value in MPa. For example, Q235 stands for carbon structural steel with a yield point (σs) of 235 MPa. (2) When necessary, symbols indicating quality grade and deoxidation method can be marked behind the steel grade.

4. Quality grade symbols are A, B, C and D respectively. Deoxidation mode symbol: f stands for boiling steel; B stands for semi-killed steel; Z stands for killed steel; TZ stands for special killed steel, and killed steel can be left unmarked, that is, Z and TZ can be left unmarked. For example, Q235-AF stands for Class A boiling steel.

Extended data:

When mechanical parts are installed on concrete foundation, one end of J-shaped and L-shaped bolts is buried in concrete for use.

The tensile capacity of anchor bolts is the tensile capacity of round steel itself, and its size is equal to the cross-sectional area multiplied by the allowable stress value (Q235b: 140mpa, 16mn or Q345: 170mpa), which is the allowable tensile bearing capacity in the design.

The anchor bolts are generally made of Q235 steel, which is round. Rebar (Q345) has great strength, so the thread of nut is not as easy as round thread. For a round anchor bolt, the burial depth is generally 25 times its diameter, and then a 90-degree hook with a length of about 120mm is made.

If the diameter of the bolt is large (such as 45mm) and the buried depth is too deep, a square plate can be welded at the end of the bolt, which can be made into a big head (but there are certain requirements). Buried depth and hook are to ensure the friction between the bolt and foundation, so as not to pull out the bolt.

References:

Baidu encyclopedia-anchor bolt