Hot dip galvanized bridge is an engineering miracle that is corrosion-resistant and durable!
Publish Time: 2025-03-13
Knowledge Popularization of Hot dip galvanized bridge
Bridges play a vital role in modern infrastructure construction. Whether it is a large transportation hub across rivers, lakes and seas, or a small bridge connecting city streets, they have provided great convenience for people's lives and economic development. However, bridges have been exposed to the natural environment for a long time and face various severe challenges, among which corrosion is particularly prominent. In order to extend the service life of bridges and ensure their safe operation, hot dip galvanizing technology has been widely used in bridge construction and maintenance. This article will introduce the relevant knowledge of Hot dip galvanized bridge in detail, including its principles, advantages, production process and maintenance points.
1. Principle of Hot dip galvanized bridge
Hot dip galvanizing is a method of immersing a steel structure in molten zinc to form a protective layer of zinc-iron alloy. When steel is immersed in liquid zinc, zinc will form a uniform and dense zinc-iron alloy layer on the surface of the steel. This alloy layer can effectively isolate the steel from the external environment, thereby playing an anti-corrosion role. This anti-corrosion method utilizes the electrochemical properties of zinc, because zinc is easily oxidized in the air to form a stable zinc oxide film, which can further prevent oxygen and moisture from corroding the steel.
2. Advantages of Hot dip galvanized bridge
Excellent anti-corrosion performance: The hot dip galvanized layer can provide long-term anti-corrosion protection for the bridge steel structure. Since zinc has a lower potential than iron, zinc will preferentially undergo an anodic reaction in an electrolyte environment, thereby protecting the steel matrix from corrosion. Even if the hot dip galvanized layer is partially damaged, the zinc layer can continue to protect the surrounding steel by sacrificial anodes. This characteristic makes the hot dip galvanized bridge have excellent corrosion resistance.
Good durability: The bridge steel structure treated with hot dip galvanizing can be used for a long time under normal use conditions without frequent anti-corrosion maintenance. Generally speaking, a qualified hot dip galvanized layer can ensure that the bridge maintains good performance for decades, reducing maintenance costs and workload.
Enhance structural safety: Hot dip galvanizing can not only prevent the corrosion of steel, but also improve the strength and hardness of steel to a certain extent. This is because during the hot-dip galvanizing process, the formation of the zinc-iron alloy layer changes the microstructure of the steel surface, making it denser and more uniform, thereby improving the mechanical properties of the steel and enhancing the overall safety of the bridge.
3. Production process of hot dip galvanized bridge
At present, the main production process of hot-dip galvanized steel wire products for bridge cables at home and abroad is: wire rod surface treatment - wire drawing - hot-dip galvanizing - stabilization treatment. The specific operation steps are as follows:
Wire rod surface treatment: Select suitable wire rods as raw materials, remove impurities such as oil and scale on the surface, ensure the cleanliness of the wire rod surface, and provide a good foundation for the subsequent hot-dip galvanizing process.
Wire drawing: The wire rod is stretched to the required diameter size through a wire drawing machine. In this process, it is necessary to strictly control the speed, tension and other parameters of wire drawing to ensure the mechanical properties and surface quality of the steel wire.
Hot-dip galvanizing: This is a key process. The treated steel wire is sent to the hot-dip galvanizing production line, first the I-shaped wheel is released, then it goes through the lead liquid degreasing, pickling, water washing, plating assistance, drying and other links in sequence, and finally enters the hot-dip galvanizing furnace for galvanizing. In this process, factors such as the temperature of the zinc liquid and the galvanizing time of the steel wire will affect the quality of the galvanized layer, so these parameters need to be accurately controlled.
Stabilization treatment: The galvanized steel wire needs to be stabilized to eliminate the internal stress generated during the galvanizing process and improve the bonding strength and stability of the galvanized layer.
Finished product inspection: The quality inspection of the produced hot-dip galvanized steel wire includes appearance inspection, dimension measurement, galvanized layer thickness detection and other items to ensure that the product meets the relevant technical standards and requirements.
4. Application examples of hot dip galvanized bridge
Hot-dip galvanizing technology is widely used in bridge construction. For example, in the construction of large cross-river bridges, key components such as cables and steel box girders of bridges are usually treated with hot-dip galvanizing technology for corrosion protection. Take a Yangtze River Bridge as an example. Its main cable is composed of a large number of high-strength galvanized steel wires. After being processed by a precise hot-dip galvanizing process, these steel wires not only have good anti-corrosion performance, but also can meet the requirements of high strength, ensuring the safe operation of the bridge in a complex and changing environment. Another example is the overpass in a certain city. Its steel structure is treated with hot-dip galvanizing. After years of use, it still maintains good performance and no obvious corrosion occurs. This fully proves the effectiveness of hot-dip galvanizing technology in bridge anti-corrosion.
5. Maintenance points of hot dip galvanized bridge
Although hot dip galvanized bridge has good anti-corrosion performance, it still needs proper maintenance and management during long-term use to ensure that it always maintains a good condition.
Regular inspection: Regular comprehensive inspection of the bridge is an important part of maintenance work. The inspection content includes the surface condition of the steel structure, the tightening of the connection parts, the integrity of the anti-corrosion coating, etc. Through regular inspection, potential problems can be discovered in time and corresponding measures can be taken to deal with them.
Cleaning and maintenance: It is also very important to keep the steel structure of the bridge clean. Regularly clean the dust, dirt, and debris on the surface of the steel to prevent these substances from adhering to the surface of the steel for a long time and affecting the protective effect of the hot-dip galvanizing layer. At the same time, for some easily contaminated parts, such as the bottom of the bridge and around the drainage holes, the cleaning efforts should be increased.
Anti-corrosion repair: Even with the protection of the hot-dip galvanizing layer, the steel structure may suffer from local corrosion or coating damage over time and under the influence of the environment. Once these problems are found, anti-corrosion repair treatment should be carried out in time. For parts with less corrosion, grinding, rust removal, and repainting can be used for treatment; for parts with severe corrosion, damaged parts need to be replaced.
Load management: Reasonable control of the load of the bridge is also one of the important contents of maintenance work. Excessive load will accelerate fatigue damage and deformation of the steel structure and affect the service life of the bridge. Therefore, during the use of the bridge, the weight and speed of the vehicle must be strictly limited in accordance with the design regulations to avoid overloading.
The application of hot-dip galvanizing technology in bridge construction provides an effective solution for the anti-corrosion protection of bridges. It has the advantages of excellent anti-corrosion performance, good durability and enhanced structural safety. Through reasonable production process and strict quality control, high-quality Hot dip galvanized bridge products can be produced. In practical applications, it is also necessary to strengthen the maintenance and management of Hot dip galvanized bridges, and regularly conduct inspections, cleaning, anti-corrosion repairs, etc. to ensure the safe operation and long-term service life of the bridge. With the continuous advancement of science and technology, it is believed that the application of hot dip galvanizing technology in the field of bridges will continue to improve and develop, and make greater contributions to my country's infrastructure construction.
