It can be seen from the function and acceptance specification of diagonal braces that diagonal braces should be set when the suspender of indoor ceiling is more than1.5m. The general practice of diagonal braces is not clear in the construction specification. The usual practice can be calculated by the design institute as Φ12 reinforcement, angle iron, square steel and so on connected with the main keel.
According to the Code for Acceptance of Construction Quality of Building Decoration Engineering (6. 1. 1 1), the distance between the boom and the end of the main keel is not more than 300mm, and when it is more than 300mm, a boom should be added. When the length of the boom is greater than 1.5m, the bracing shall be set. When the boom meets the equipment, the boom should be adjusted and added. It is also stipulated that it is suitable for the transfer floor structure with connection above 3 m, and the function of anti-diagonal brace is mainly to control the ceiling board to move upward when negative wind pressure is generated indoors. When the board is subjected to wind load, it will float up and down. Generally, suspenders are made of φ6~ 10 steel bars, which can control the face-down movement, but cannot control the face-up movement. Reverse brace can support the board surface and prevent it from moving upward, thus controlling the deformation of the board surface.