What Are The Characteristics Of The Steel Temporary Bridge?

The temporary steel bridge is defined by the manufacturing material. The main feature of the temporary steel bridge is modularity, and the scope of the temporary steel bridge is wider. From the literal understanding, it can be basically said that the main body of the steel structure bridge can be called the temporary steel bridge. It's just that the steel temporary bridge is more typical and has the widest application.

The convenient steel bridge is made of high-strength steel and is made up of lightweight standardized truss unit components and beams, longitudinal beams, bridge decks, bridge seats and connectors. With special installation equipment, it can be quickly assembled on site to be suitable for various spans and loads. Truss girder bridge. In the Second World War, it was used extensively in the battlefields of Europe and the Far East to repair bridges or erect temporary bridges. After the war, the Bailey bridge was improved and converted to civilian use. The improved version in the United States is named the Akroger bridge. The Chinese highway department uses 16mn steel to design and name the prefabricated highway steel temporary bridge. A set of equipment can be used to erect single-lane bridges with spans of 9, 12, 15...60, 63 meters. Class, crawler 50, trailer 80 load. This kind of bridge component is also widely used as construction support or tower.

The connection mode of the temporary steel bridge is different from the connection mode of other bridges. So, what are its characteristics?

1) The advantage of steel bridge welding is that it is convenient to use the steel from any orientation, angle and shape intersection. Generally, no additional connecting plate is needed to connect the angle steel parts, and there is no need to open holes in the steel, so that the section will not be weakened. .

2) Bolt connection can be divided into ordinary and high-strength bolt connection. Advantages, easy installation, especially suitable for site installation and connection. Disadvantages, it is necessary to make holes on the plates and to align the holes during assembly, which increases the manufacturing workload; the bolt holes also weaken the cross section, and the connected plates need to be overlapped with each other or additional angle steel or assembling plate connecting pieces, Scrap steel.

3) Rivet connection; rivets are usually made of ordinary carbon rivet steel ML2 or ML3 with good plasticity and upsetting performance, and the hole diameter is used as the nominal diameter of the rivet. Plasticity, toughness and integrity are good, connection deformation is small, force transmission is reliable, fatigue performance under load is good, and the quality is easy to check. Disadvantages: complex structure, large amount of steel, troublesome construction, loud noise when rivets, and poor working conditions.

Accessible steel bridges can be divided into beam bridges, arch bridges, steel bridges, cable-stayed bridges, suspension bridges, and hybrid system bridges according to the stress system of the main load-bearing structure;

1) Under the action of vertical load, the beam bridge has only bending moment and shear force in the cross section of the main girder, and no axial orce is generated. The support only bears the force in the vertical direction, not the horizontal force.

2) The biggest difference in the force of an arch bridge is that under the action of a vertical load, in addition to the vertical reaction force at the two ends of the arch, there is also a horizontal thrust, which greatly reduces the bending moment and shear force in the arch. , Mainly under pressure.

3) The force of steel structure bridge has some characteristics of beam bridge and arch bridge, and the main load-bearing structure is eccentric compression and bending.

4) For cable-stayed bridges, the cables are under tension, the beams are bent, and the tower is under compression.

5) Suspension bridge, the meeting of the suspension cable only bears the tensile force.