Materials for reinforcing bridges can be divided into three main categories based on their function: enhancing structural strength, bonding new and old components, and assisting in reinforcement construction. The specific classifications and details are as follows:

Reinforcing materials (core load-bearing materials) 

These materials directly improve the load-bearing capacity, stiffness, and durability of bridge components, and are the core of reinforcement:

1. Fiber Reinforced Polymer (FRP) Composites

• Carbon Dioxide Reinforced Polymer (CFRP): High strength, lightweight, and corrosion-resistant; suitable for reinforcing beams under bending and shear stresses, as well as in highly corrosive environments (coastal areas, bridges near chemical plants). Including carbon fiber sheet, carbon fiber laminate, carbon fiber anchor, carbon fiber jacket, carbon fiber mesh, carbon fiber cable, carbon fiber rod and prestresse carbon fiber plate system.

• Glass Fiber Reinforced Polymer (GFRP): Lower cost than CFRP; acid and alkali resistant; suitable for temporary or semi-permanent reinforcement in humid environments.

• Aramid Fiber Reinforced Polymer (AFRP): High toughness and impact resistance; suitable for bridges with high seismic requirements or those susceptible to impact (such as overpasses).

2. Steel Materials

• Steel Plates: Thin steel plates are used for steel-plate bonding reinforcement; thick steel plates can be used in conjunction with methods to enlarge the cross-section.

• Structured Steel (Angle Steel, Channel Steel): Reinforces the beam structure through external wrapping, suitable for bridges with severely insufficient load-bearing capacity.

• Reinforcing Steel Bars: Used in conjunction with high-performance concrete to enlarge the cross-section for reinforcement, improving the overall structural integrity.

3. High-Performance Concrete Categories:

• High-Strength Concrete (≥C50): Used to increase the cross-section of beams and piers, and to repair structural defects.

• Self-Compacting Concrete: Requires no vibration; suitable for pouring in areas with dense reinforcement and limited construction space.

• Shotcrete: High-pressure shotcrete application; suitable for repairing damaged beam surfaces and thickening thin-walled components.

Bonding Materials (Ensuring Coordinated Load-Bearing)

These materials are crucial for connecting the original bridge structure to the new reinforcement materials, ensuring that the old and new components share the load:

• Epoxy Structural Adhesives: High bonding strength, aging resistant, used for bonding steel and FRP sheets.

• Modified Epoxy Adhesives: Suitable for construction in low-temperature and humid environments.

• Interface Agents: Enhance the bond between new and old concrete, used for interface treatment in cross-sectional reinforcement.

Auxiliary Materials (Completing the Reinforcement System)

While these materials do not directly bear stress, they enhance the reliability and stability of the reinforcement:

• External Prestressing Materials: Steel strands and prestressed steel bars, used for external prestressing reinforcement to offset tensile stress in the beam and reduce deflection.

• Anchoring Materials: Anchor bolts and rigid anchorage, used to secure the ends of FRP sheets and steel plates, preventing the reinforcement material from peeling or slipping.

• Corrosion and Rust Prevention Materials: Rust-proof paint and anti-corrosion coatings, used to protect steel reinforcement materials.