Anchor bolt (fastener)

When the mechanical components are installed on the concrete foundation, the J-shaped and L-shaped ends of the bolts are buried in the concrete for use.  

The tensile capacity of the anchor bolt is the tensile capacity of the round steel itself, and the size is equal to the cross-section area multiplied by the allowable stress value (Q235B:140MPa, 16Mn or Q345:170MPA) is the allowable tensile capacity of the design.  

Anchor bolts generally use Q235 steel, that is, light round.  Rebar (Q345) is of great strength, making the thread of nut is not as easy as light round.  For the round anchor bolt, the buried depth is generally 25 times its diameter, and then make a 90 degree hook about 120mm long.  If the bolt diameter is very large (such as 45mm) buried too deep, you can weld the square plate at the end of the bolt, that is, a big head can be (but there are certain requirements).  The buried depth and the bent hook are to ensure the friction between the bolt and the foundation, so as not to pull out the bolt damage.