The calculation of single bolt shows that the tensile strength and shear strength of high strength bolt are lower than that of ordinary bolt. The essence of its high strength is that no relative slip is allowed to occur at the node during normal operation, that is, the elastic-plastic deformation is small and the node stiffness is large.
It can be seen that in the case of a given design node load, the joints designed with high-strength bolts may not necessarily save the number of bolts, but they have small deformation, large stiffness and high safety reserve. Suitable for main beam, such as the requirements of the node stiffness of the position, in line with the "strong node, weak member" of the basic seismic design principle.
The strength of high-strength bolt lies not in the design value of its bearing capacity, but in the stiffness of its design joints, high safety performance and strong ability to resist damage.