Rubber Waterstop

A flexible waterproof sealing strip made of synthetic rubber (e.g., EPDM, Neoprene, or Natural Rubber), designed to prevent water leakage at construction joints in concrete structures (e.g., dams, tunnels, basements).

Key Types

1. Centerbulb Waterstop

• Hollow "bulb" compresses to seal under hydrostatic pressure.

• Used for dynamic joints (movement ±15mm).

2. Flat Ribbed Waterstop

• Surface ribs enhance bonding with concrete.

• For static joints (minimal movement).

3. Dumbbell Waterstop

• Dual bulbs for high-pressure zones (e.g., reservoir walls).

4. Expansive Waterstop

• Contains water-swelling additives (e.g., bentonite) for self-sealing cracks.

Material Properties

Typical Dimensions:

• Width: 150–400 mm

• Thickness: 5–15 mm

• Tensile Strength: ≥10 MPa (ASTM D412)

Installation Guidelines

1. Embedment:

• Must be fully encased in concrete (no exposed sections).

• Splice joints require vulcanization or adhesive bonding.

2. Joint Types:

• Construction Joints: Centerbulb profile (allows movement).

• Expansion Joints: Dumbbell profile (handles shear stress).

3. Compatibility:

• Avoid contact with petroleum-based solvents (degrades rubber).

Standards & Testing

• ASTM D4635 (Rubber waterstop physical testing)

• GB 18173.2 (Chinese standard for waterstops)

• EN 14841 (European waterstop specifications)

Performance Metrics:

• Watertightness: ≥0.8 MPa pressure resistance (per ASTM D5385).

• Elongation at Break: ≥300% (ensures flexibility).