- For a weight of 900 tons, some friends may not have a clear concept. Let me give you an analogy. Usually, the cars we drive weigh about 1.5 tons each. And installing a girder is equivalent to 600 cars in the air. Therefore, when transporting box girders, the engineering team also used specialized transport vehicles – beam transport vehicles. The Bridge Girder Carriers mainly divided into two types: track type and tire type. When we transport girders weighing up to 900 tons. We use Bridge Girder Carrier, which can reach a maximum speed of 5 kilometers per hour. So, how is a box girder weighing 900 tons placed on a bridge pier?
How the box girder erected
- During the installation process of the 48-meter-long bridge girder. Two construction techniques used: feeding beams under the bridge and feeding beams on the bridge. Feeding girder refers to the process where the Bridge Girder Carrier directly delivers the girder to the bridge launcher. This process like feeding fish, hence it called “feeding beams”. And the feeding of beams on the bridge carried out when the road under the bridge impassable. Subsequently, the engineering personnel stably placed the box girder on the load-bearing part of the bridge erecting machine, and then moved the forearm of the machine between the two bridge piers to perform the subsequent hole by hole assembly work. This process seems simple on the surface. The key difficulty in installing box girders lies in their stability and accuracy. During the process of lifting the bridge girder, due to the increase in axle load and the soft soil of the newly built embankment, reinforcement measures must taken, such as using heavy vehicles to compact the road and adding track sleepers, to prevent problems such as the bridge girder tilting or box girder tilting. During construction, the box girder must also installed at the precise position specified in the engineering drawings, and any error must be controlled within 1 centimeter, otherwise it will cause serious engineering safety hazards. Therefore, during the operation process, construction personnel must maintain a high level of vigilance and focus.
Finally, to assist in the installation of the gantry crane box beams, we have developed two 1800-ton gantry cranes, marking the world’s first complete set of equipment technology for 1800-ton steel beam erection. The continuous progress of bridge construction technology by China Railway has also provided important impetus for the rapid development of high-speed railways.