What is the Anti-corrosion Principle of Galvanized PC Steel Strands？

The corrosion resistance of galvanized PC steel strand mainly depends on the protection mechanism and process design of its galvanized layer, the process of single steel wire passing through the zinc bath is called hot-dip galvanizing, and the galvanized PC steel strand is twisted by 7 hot-dip galvanized steel wires. The adhesion of zinc layer is checked according to the wrapping test of the galvanized PC steel wire before twisting or the central steel wire of the finished galvanized steel strand. After 6 turns of winding, the zinc layer of the spiral ring shall not peel off. The specific reasons are as follows:

Ⅰ. Process and Performance Advantages

1. Hot-dip Galvanizing Process: The zinc layer is evenly covered on the surface of the steel strand, including recessed and sharp corners, to avoid local corrosion, thereby improving its toughness and reducing the risk of mechanical damage during transportation and construction.

2. Maintaining Mechanical Properties: After galvanizing, the tensile strength of the steel strand can still reach 1860-2100MPa, and the low relaxation characteristics ensure its long-term stress stability.

Ⅱ. Anti-corrosion Principle and Characteristics

1. Sacrificial Anode Protection Substrate: The galvanized layer (zinc layer weight 190–350g/m²) protects the steel strand substrate through the principle of sacrificial anode, forming a dense zinc oxide (ZnO) film on the surface of the steel strand to isolate the corrosive medium and avoid rust.

2. Corrosion-resistant Environmental Adaptability: The galvanized layer can resist chloride ion erosion in marine climate and coastal projects. In humid and salt spray environments, the service life can be extended to more than 50 years. The zinc layer can effectively inhibit the corrosion of steel strands.

Ⅲ. Environmental Adaptability

1. General Corrosive Environment: galvanized steel strands can be directly used in conventional projects such as bridges and tunnels without additional coating.

2. Severe Corrosive Environment: composite protection is required, that is, in the ocean or high chloride ion environment, the galvanized layer is combined with HDPE casing and anti-corrosion grease to form a multi-layer protection to protect the steel strand matrix and prevent rust.

IV. Comparison with Other Anti-corrosion Measures

1. Unbonded Steel Strand: Relying on HDPE sheath and anti-corrosion grease, but poor sealing of the anchor end can easily lead to corrosion, and the galvanized layer can make up for this defect.

2. Epoxy-coated Steel Strand: Compared with epoxy-coated steel strand (high manufacturing difficulty and high cost), the galvanizing process is more economical and convenient to construct.

Summary

Galvanized PC steel strands have excellent corrosion resistance through sacrificial anode protection of the zinc layer and process optimization, and are suitable for a variety of harsh environments. Its corrosion resistance can be verified by stress corrosion tests and zinc layer adhesion tests, and is superior to epoxy coatings and other solutions in terms of cost and construction efficiency. The galvanized PC steel strands produced by our factory strictly follow the production process, have excellent corrosion resistance, and are widely used. If you need this type of PC steel strand, please contact us. We provide you with professional products and services. If you are interested in understanding or inquiring, please feel free to contact us by email or phone! View our website https://www.yxmaterial.com to find the products you need, request a quote, or contact us for more assistance or additional information.