The composition of Beret films

　　Beret plate is welded by upper and lower chord, vertical rod and inclined rod. The upper and lower chord ends are connected with Yin and Yang joints, and the joints are connected with a pestle and a pin hole. Guizhou berea piece of channel steel chord by two 10 (back), on the lower chord, how block welding steel plate with circular hole, in strengthening the chord and bottom chord from and double-deck truss connecting bolt hole, within the upper chord and four bolt holes for connecting racks, between the two holes is for double row or more rows of truss with internode connection. The two holes at each end are interjointed across the nodes. When multiple rows of beret plates are used as beams or columns, the joints of upper and lower beret plates shall be strengthened with a support frame.

　　On the lower chord, there are four beam backing plates with a convex tenon above to fix the position of the beam on the plane. On the end channel steel web of the lower chord, there are also two elliptical holes for connecting the wind-resisting pull rod. The vertical rod of Beret plate is made of 8# I-steel, and there is a square hole on the side of the vertical rod near the lower chord, which is used for the beam fixture to fix the beam. The material of Guizhou Beret tablet is 16Mn, and each frame weighs 270kg.

　　"321" steel bridge is prefabricated highway steel bridge, its characteristics are: lightweight components, easy to disassemble and assemble, strong adaptability, with simple tools and manpower can be quickly built. It is suitable for five kinds of loads, such as car-10, car-15, car-20, crawler-50 and trailer-80. The net width of the carriageway on the bridge deck is 3.7m, which can be combined into a variety of span simply supported beam Bridges within 9m to 63m, and the continuous beam Bridges can be constructed.