Bolting is the preferred method of Steel connecting members on the site. Staggered bolt layout allows easier access for tightening with a pneumatic wrench when a connection is all bolted. High strength bolts may be snug-tightened or slip-critical.
Snug-tightened connections are referred to as bearing connections Bolts in a slip-critical connection act like clamps holding the plies of the material together.Bearing type connections may have threads included ( Type N ) or excluded ( Type X ) from the shear plane(s). Including the threads in the shear plane reduces the strength of the connection by approximately 25%.
Loading along the length of the bolt puts the bolt in axial tension. If tension failure occurs, it usually takes place in the threaded section.Three types of high strength bolts A325, A490 (Hexagonal Head Bolts), and F1852 (Button Head Bolt). A325 may be galvanized A490 bolts must not be galvanized F1852 bolts are mechanically galvanized.
High strength bolts are most commonly available in 5/8” – 1 ½” diameters. Bolting requires punching or drilling of holes. Holes may be standard size holes, oversize holes, short slotted holes, long slotted holes.
Post a Comment