What are the functions of box girder in the production of bridge formwork

The bridge formwork is made up of three parts: the bottom mold, the outer mold, and the inner mold: the first is the bottom mold. The box girder can be poured with more than 530 tons of concrete at a time. In addition, the girder bridge template weighs more than 90 tons and the construction load per square meter is 1.5KN. The bottom form has a load of more than 27 tons per linear meter. In order to make the bottom bridge formwork rigidity and meet the requirements of uniform force, the bottom form panel adopts 12mm thick steel plate and channel steel to form a well-shaped integral welded structure, and the steel structure bottom beam is used to transfer the force of the bottom form to the base of the pedestal. The well-shaped structure is made in sections, which is convenient to adjust the flatness and the inverted camber of the bottom mold.

The inverted arch of the bottom formwork is arranged in a broken line according to the sections of the bottom formwork. At the same time, in order to evenly transmit the force of the bridge formwork to the foundation, a three-point supported I-shaped bottom beam is used to effectively integrate the concrete foundation into a whole. It not only increases the rigidity of the bottom form, but also increases the lateral rigidity of the concrete strip foundation, and at the same time saves the amount of steel. The spacing of the beams is 800mm.

The panels are assembled using tool-type steel bridge formworks to form an integral internal mold on the ring-shaped steel frame. The installation and use method of the assembled inner mold: first assemble the skeleton, and then lay the panel. The assembly accuracy of the skeleton directly affects the overall accuracy of the internal mold. When assembling, the positions of the four points are controlled accurately, and the upper and lower lines are parallel to each other to ensure the accuracy of the skeleton. For this reason, four kinds of assembling molds for the skeleton are specially made. The frame is hoisted in sections, and after the alignment is good, adjust the frame with positive and negative screw rods. The advantages of this: fast, convenient, and high precision.