Corrugated pipe for railway prestressed concrete φ90mm bridge plastic corrugated pipe

Corrugated Pipe for Railway Prestressed Concrete φ90mm Bridge Plastic Corrugated Pipe

Plastic Corrugated Pipe for Prestressed Concrete Beams

The plastic corrugated pipe (typically made of HDPE or PP) used in prestressed concrete beams is a duct-forming material for post-tensioned prestressed structures, primarily used to protect prestressed steel strands or rebars and ensure grouting compactness. Below are its key features and application points:

1. Material and Characteristics

• Material: High-density polyethylene (HDPE) or polypropylene (PP), featuring corrosion resistance, good flexibility, and strong impact resistance.
• Structure: Spiral corrugated design enhances compressive strength and facilitates bending during construction.
• Advantages:
  • Resistant to acids, alkalis, and aging, with a long service life (superior to metal corrugated pipes).
  • Low friction coefficient, reducing prestress loss.
  • Good insulation, preventing galvanic corrosion (suitable for environments with stray currents).

2. Technical Standards

• Chinese Standards:
  • "JG/T 225-2020" Plastic Corrugated Pipes for Prestressed Concrete (latest version).
  • Must meet performance requirements such as ring stiffness, local transverse load, and flexibility.
• International Standards: Such as ISO 14839 (some countries reference ASTM or EN standards).

3. Construction Key Points

• Installation:
  • Fix according to design positions to avoid displacement during concrete pouring.
  • Joints should be thermally fused using dedicated sleeves to ensure sealing.
• Grouting:
  • Pipes must be clear and unobstructed; grouting materials should use high-performance non-shrink cement slurry.
  • Check compactness after grouting (detectable via ultrasonic or impact-echo methods).

4. Application Scenarios

• Bridge Engineering: Long-span beams, continuous beams, cantilever beams, etc.
• Building Structures: Transfer beams in high-rise buildings, long-span slabs.
• Special Environments: Corrosive environments such as coastal areas and chemical plants.