Development trend of bridge coatings

As to the development of high-speed, electrification railway, higher request of steel bridge maintenance, overhaul, can't be as often as before operation on the bridge, which require development better anticorrosion performance and longer service life of coating system, in the process of the steel bridge using only the primary and secondary protection coating, at the same time should be developed to the environment pollution of small water-based paint, environmental protection coating.

1, high performance coating

Such as room temperature curing fluorocarbon coating, it has exceptional weather resistance, outstanding salt spray resistance, excellent resistance to chemical medium and good resistance to stain and erosion resistance.Domestic fluorocarbon coatings in the main performance and foreign products still have a certain gap, so we should strengthen the fluorocarbon coatings especially fluorocarbon resin research and development efforts, the production of a real sense of fluorocarbon coatings.

2, water-based coating

With the continuous improvement of living standards, people's awareness of environmental protection is also increasing, the use of waterborne coatings for steel bridge coating is an inevitable trend.Waterborne inorganic zinc-rich paint has been widely used in steel structure processing in China as a precoating primer, and has also been used as a matching primer for steel Bridges in China. However, there are still some problems in application, such as brittle coating, poor compatibility with other coatings, etc., which need further improvement and research.

3, composite protection materials

The surface of steel bridge is arc sprayed with metal and then coated with topcoat.Metal spray protection began in 1910 and has a history of more than 90 years.In the 1930s, zinc spray coating was widely used abroad and then aluminum spray coating was used to protect railway and highway Bridges, various hydraulic steel structures and hydropower station equipment, petrochemical equipment and ships.It has been used for 50 years in China since the 1950s.The practice has proved that spraying metal anticorrosion is a kind of long - term and suitable anticorrosion method.After more than 90 years of development, spray metal can not only spray zinc, spray aluminum, spray aluminum alloy, spray aluminum magnesium alloy and spray aluminum rare earth alloy;In the spraying process also gradually developed from flame spraying to arc spraying and even high speed arc spraying.In recent years, arc spraying metal repaint has been applied in ports, wharves and Bridges in China, such as the Guangdong-Hai trestle project.

4, railway reinforced concrete bridge protection materials

Now the design life of the railway reinforced concrete bridge is the same as that of the steel bridge, which is 100 years. In addition, the concrete bridge on the existing line also appears corrosion and other damage to varying degrees.Therefore, it is necessary to repair or protect it. One of the main protection measures is to develop protective coating and develop the corresponding construction technology.