What Are the Criteria for Surface Treatment of Prestressed Steel Strand?

As a supplier specializing in prestressed steel strand production, we understand that choosing the right surface treatment is crucial to ensuring project safety and durability. Drawing on years of experience in service projects, we've summarized the following criteria to help you find the optimal solution:

1. Corrosion Level of the Project Environment

- For dry, non-corrosive environments (such as floor slabs and beams in ordinary buildings): Plain prestressed steel strand is a cost-effective option. The concrete cover alone can meet foundation corrosion protection requirements, making it fully suitable for conventional civil construction. Our plain steel strand boasts a mature process, strong adaptability, and a competitive price-performance ratio.

- For humid/mildly corrosive environments (such as bridges and dams): Galvanized prestressed steel strand is an ideal choice. The 80-120μm thick zinc coating provides sacrificial anodic protection, achieving a corrosion life 3-5 times that of ordinary steel strand in salt spray testing, making it easily resistant to rain and water vapor erosion. Our advanced galvanizing process ensures a uniform and durable zinc layer, ensuring guaranteed protection.

- For highly corrosive environments (such as coastal projects, chemical plants, and nuclear power plants): Coated steel strands (such as epoxy-coated or polyethylene-jacketed) are recommended. The epoxy coating (0.6-0.8mm) or polyethylene jacket on these strands physically isolates chloride ions and chemical agents. For example, our epoxy-filled steel strands are guaranteed to resist rust for over 50 years in such environments. Unbonded steel strands also feature a polyethylene jacket with excellent sealing properties and are equally durable, providing reliable protection for the project.

2. Construction Technology (Pre-tensioning/Post-tensioning)

- Pre-tensioning construction (e.g., precast beams and slabs): Prestress is transferred through the bond between the steel strand and concrete. Indented prestressing strands, with circular indentations spaced 5-10mm apart, achieve 20%-30% greater adhesion than smooth strands, while maintaining a slippage of less than 1mm, ensuring precise prestress transfer. Our indenteded strands feature uniform notches and stable bonding, making them particularly suitable for pre-tensioning construction.

- Post-tensioning construction (e.g., cast-in-place bridges and large frames): Stress is transferred through anchors, requiring less stringent bond strength. Smooth prestressing strands are sufficient. Their smooth surface allows for easy stranding, shortening construction time and reducing labor costs. Our smooth strands feature a meticulously finished surface, making stranding easier and improving construction efficiency.

3. Project Durability Requirements

- For short-term use or low-maintenance structures (such as temporary supports and low-rise buildings): Plain or galvanized steel strands are sufficient, ensuring foundation durability and meeting the lifespan of the foundation. Our two types of steel strands are of exceptional quality and reliable for short-term use.

- For long-term use (design life of 50 years or more) or high-maintenance structures (such as underground utility tunnels and offshore platforms): Coated steel strands with enhanced corrosion resistance can be selected. For example, our monofilament epoxy steel strands have undergone aging testing and provide long-term protection in harsh environments, ensuring the project lifespan perfectly matches design expectations and reducing maintenance hassles.

In general, the selection process should consider environmental corrosion, construction process, and durability requirements. We will develop a suitable solution for your project at no charge, ensuring the selected strand meets your project requirements. Feel free to contact us with any questions. We will do our best to provide satisfactory products and services, and provide professional solutions to safeguard your project!