Quality control of high strength bolt connection of steel structure mainly includes

(1) The type, specification and technical conditions of high-strength bolts must meet the design requirements and relevant standards. High-strength bolts must be tested to determine the torque coefficient or double-check the pre-tension of bolts. When the result is in line with the special provisions of high-strength bolts for steel structure, it is allowed to be used.

(2) The friction coefficient of the connecting surface of the high-strength bolts of the member must meet the design requirements. The surface is strictly prohibited to have oxidized iron skin, burr welding scars and oil contamination.

(3) High-strength bolts must be tightened twice, and the quality of initial and final tightening must be in accordance with the construction specification and the special provisions of high-strength bolts for steel structure.

(4) Appearance requirements of high-strength bolt joints: the direction of bolt penetration is the same on the front side, and the exposed length is not less than 2 buckles.