Composition And Application Of Steel Box Girder

Steel box girder, also known as steel plate box girder, is a common structural form of long-span bridges. Generally used on bridges with large spans, it is called steel box girder because it looks like a box.

1. The main components of steel box girder

Steel box girders are generally made of top plate, bottom plate, web plate, transverse diaphragm, longitudinal diaphragm and stiffeners connected by full welding. The top plate is an orthotropic bridge deck composed of a cover plate and longitudinal stiffeners.

The thickness of each plate of a typical steel box girder can be as follows: the thickness of the cover plate is 14mm, the thickness of the longitudinal U-shaped rib is 6mm, the width of the upper opening is 320mm, the width of the lower opening is 170mm, the height is 260mm, and the spacing is 620mm; the thickness of the bottom plate is 10mm, and the longitudinal U-shaped stiffening rib is 10mm. ; The thickness of the inclined web is 14mm, the thickness of the middle web is 9mm; the distance between the diaphragms is 4.0m, and the thickness is 12mm; the beam height is 2-3.5m.

Steel plate box girder is a structural form often used in engineering. In order to study the effect of diaphragm spacing on the distortion of simply supported steel box girder under concentrated load, simply supported steel box girder with different numbers of The distortion effect and rigid torsion effect under the load are obtained, and the curve of the maximum distortion effect with the number of diaphragms is obtained. A concentrated load is applied to the top of the web of the box girder, and the four conditions of distortion, rigid torsion, symmetrical bending and eccentric load are adopted. The load decomposition method is used for calculation.

2. What are the main applications of steel box girder

Due to its structural form, steel box girders are generally used for municipal viaducts and ramp steel box girders; during construction, traffic organization is used for long-span cable-stayed bridges, suspension bridges, arch bridge stiffening beams and pedestrian bridge steel box girders.