Box Girder Bridge for Overpass And Expressway

Bridge, as an increasingly important transportation facility, gradually developed from the original period, from naturally fallen trees, naturally formed stone beams or arches, to later man-made wooden bridges, stone bridges, materials are increasingly advanced. Especially steel bridge, although only more than 200 years of development history, but because of its own characteristics

Introduction

Steel beam Bridges include steel beam bridge and steel truss bridges of simply supported or continuous system. Steel girder bridges are generally processed in factories and constructed on site. There are many construction methods, including the whole hole hoisting method, bracket assembling method, cable hoisting method, turning method, pushing method, dragging method and cantilever assembling method.

Steel box girder, also called steel plate box girder, is a common structural form of long span Bridges. It is generally used on Bridges with large spans. Steel box girder bridge is more and more frequently used in highway Bridges, especially in urban overpasses and cross-line Bridges. There are mainly single box girder bridge, double box girder bridge and multi-box girder bridge. The steel box girder is generally made up of the top plate, bottom plate, web, diaphragm plate, mediastinum plate and stiffening rib, etc., which are connected by all-welding method.

Advantages of steel bridge

1) Great spanning ability

Because of the high strength of steel, and then under the same bearing capacity conditions, compared with the reinforced concrete bridge, steel bridge component section is smaller, so the steel bridge weight is light, more suitable for the construction of large-span bridge.

2) Suitable for industrial manufacturing. 

Steel bridge components are generally manufactured in specialized factories by professional equipment, not limited by the season, processing and manufacturing speed, high precision, quality is easy to control.

3) Easy to transport

Due to the light weight of steel bridge components, especially in the mountainous areas with inconvenient traffic, steel bridge is more convenient for automobile transportation

4) Erection fast

Steel bridge members are easy to cantilever construction method assembly, complete sets of equipment available, assembly process mature.

5) Steel bridge members are easy to repair and replace

The steel used in the main structure of steel bridge is mainly carbon steel and low alloy steel. Steel plates are the most commonly used in modern steel Bridges. Materials for steel bridge will go through many machining processes and welding processes, then make the bridge to be able to withstand a large static, dynamic load and impact load. Therefore, the steel materials used for Bridges should not only meet the requirements of manufacturing process, but also meet the requirements of use.