1. From the perspective of raw materials: high-strength bolts are made of high-strength materials.
2. From the strength level: high-strength bolts are increasingly used. Two intensity levels of 8.8s and 10.9s are commonly used.
3. From the perspective of the stress characteristics: high-strength bolts exert pretension and transmit external forces by friction. Ordinary bolted connections rely on the shear strength of the bolt and the bearing wall pressure to transmit the shear force. Its impact is negligible. In addition to the high strength of the data, high-strength bolts also exert a large pre-tension on the bolts, causing squeezing forces between the connecting members, thereby causing a large frictional force perpendicular to the screw direction, and Tensile force, anti-slip coefficient and steel type all directly affect the bearing capacity of high-strength bolts.