Recently, the main body of the weathering steel
box girder spanning bridge of the reconstruction and expansion project of the main line toll station of the Maojiadian main line of the Jingha Expressway, which was built by the 19th Bureau and the Third Company, was closed. The bridge is the second weather-resistant steel
box girder bridge on the expressway in Liaoning Province. It is also the first steel box girder bridge to apply the surface stabilization treatment process of weathering steel.
“The exterior of this bridge looks very inconspicuous, but it uses the domestic advanced weather-resistant special steel technology. The whole bridge uses surface stabilization treatment to form a uniform and dense rust layer on the surface of the steel plate. Then he no longer rusts, thus forming a protective layer that can resist various weather attacks.
The height of the bridge steel girder is 2.5 meters, the full width is 13.1 meters, the bidirectional transverse slope of the bridge deck is 1.5%, the box girder is in the form of equal section, the main beam is a single box double chamber steel box girder, and the bridge deck is orthotropic. Board structure. Due to the crossing of the main line toll station of Maojiadian in Jingha Expressway, the construction is high in height, complicated in structure, large in thickness of steel plate, and there are many welds and welds in the groove, resulting in large welding deformation and residual stress, and the manufacturing process. Medium control is difficult.
The steel structure of the weathering steel box girder bridge is made of Q345qENH steel. Except for the long-term anti-corrosion life (15-25) coating supporting system except for the inner surface of the beam near the beam end, the inner and outer surfaces of the steel box girder are Spray surface treatment solution is used. The chemical substance in the treatment liquid reacts with the steel matrix to form a uniform and dense protective rust layer, so that the weathering steel is more beautiful in use, and also prevents the rust liquid from polluting the environment.