Aohong is a professional manufacturer of Lead Rubber Bearings, providing high-performance seismic isolation solutions for bridges, buildings, and critical infrastructure. Lead Rubber Bearings (LRB) are composed of alternating layers of natural or neoprene rubber and reinforced steel plates, with a 99.9% pure lead core embedded in the center. The rubber layers offer flexibility and allow horizontal movement, while the steel plates provide high vertical load capacity. The lead core deforms plastically during seismic events, absorbing and converting kinetic energy into heat, which reduces structural acceleration and prolongs the vibration period. Known for durability, excellent damping, and maintenance-free operation, these bearings are widely used in highway bridges, railway bridges, high-rise buildings, and nuclear power plants to minimize earthquake damage and extend service life.
Structure of Lead Rubber Bearings
Lead Rubber Bearings are designed as laminated rubber pads combined with a central lead core for enhanced energy dissipation.
- Standard Type: Natural or chloroprene rubber with steel reinforcement.
- Sliding Type: Laminated rubber with Teflon plates for larger displacement.
- Shapes: Round and rectangular to suit different structural requirements.
- Lead Core: Single or multiple cores can be used, depending on design loads and damping requirements.
Features of Lead Rubber Bearings
- High Damping Performance: Damping ratio up to 30%, much higher than ordinary rubber bearings.
- Excellent Vertical Load Capacity: Supports 5 tons to 2000 tons while maintaining horizontal flexibility.
- Energy Dissipation: Lead core absorbs seismic energy through plastic deformation.
- Durability & Low Maintenance: Resistant to aging, corrosion, and fatigue under repeated loads.
- Seismic Isolation Efficiency: Reduces ground acceleration by extending the structural vibration period to 1.5–3.0 seconds.
- Temperature Resistance: Operates reliably in temperatures from -25 °C to +60 °C.
- Convenient Installation: No separate damper is required, making it ideal for space-constrained structures.
Lead Rubber Bearing – Load Transfer Process
Vertical Load Transfer Process
The vertical load in a Lead Rubber Bearing is transmitted through a sequential structural path, ensuring stability and efficient load distribution.
Crossbeam → Top Pre-buried Steel Plate → Top Connecting Steel Plate → Top Sealing Steel Plate → Lead Core Laminated Rubber Bearing → Bottom Sealing Steel Plate → Bottom Connecting Steel Plate → Bridge Pier.
Horizontal Load Transfer Process
The horizontal forces generated during seismic or wind loads are transferred through a separate path to maintain stability and energy dissipation.
Pier → Bottom Footing Bolt → Bottom Connecting Steel Plate → Top Sealing Steel Plate and Shear Tenon → Top Connecting Steel Plate → Top Pre-buried Steel Plate → Anchorage Member.
Specifications of Lead Rubber Bearings
| Parameter | Standard Values |
|---|---|
| Shear Modulus | 0.8 MPa, 1.0 MPa, 1.2 MPa |
| Working Temperature | -25 °C to +60 °C |
| Lead Core Quantity | Single or multiple |
| Shapes | Round, Rectangular |
| Common Sizes | 200×300 mm, 300×350 mm, 550×550 mm |
| Thickness Range | 22 mm to 150 mm |
| Load Capacity | 5 tons to 2000 tons |
Applications of Lead Rubber Bearings
- Highway and Railway Bridges – Provides effective seismic isolation and vibration control.
- High-Rise Buildings and Towers – Protects structural integrity during earthquakes.
- Industrial and Critical Infrastructure – Widely used in nuclear power plants and large-span structures.
- Curved and Skew Bridges – Round bearings are ideal for cambered or irregular bridge layouts, while rectangular bearings are suitable for straight-span bridges.
