U-bolt And Pre-camber Setting

U-bolt selection and embedment. U-shaped bolts contain two kinds, one for fixing the front end of the positioning function, one for fixing the back end of the anchoring function. The design and calculation are mainly carried out for the U-shaped bolt which plays the anchoring role at the fixed back end to ensure that its pulling strength meets the requirements while retaining a certain surplus. U-shaped bolts should be arranged in the position of the primary and secondary beams to avoid damage to the main structure. The U-shaped bolt and the main steel bar are crossed. Therefore, arrange the crossing operation according to the actual situation of the steel bar on site to avoid the failure of the U-shaped bolt installation. After the installation is complete, check the number, location and main reinforcement of U-shaped bolts to avoid the failure to install the Beret frame in the later stage.

Pre-camber design.

① Deflection of wrong hole: According to the principle of virtual work, the deflection of overhanging wrong hole fm = n (n+1) mm.

② Deflection under load: Considering that the upper load is simplified as a uniform load, the deflection at the end of the cantilevered beam fz = ql ^4/ (8EI).

③ precamber of cantilever Beret frame f = fm+fz+fg.