BS 5400 is a former British Standard used for the design and construction of steel, concrete, and composite bridges. While it has been largely superseded by the Eurocodes (specifically BS EN 1992-2 for concrete bridges), it is still frequently referenced for the assessment of existing structures or in regions that continue to follow British standards.

  1. Minimum reinforcement: The minimum amount of reinforcement required to ensure ductility and resistance to cracking.
  2. Maximum reinforcement: The maximum amount of reinforcement allowed to prevent over-reinforcement.
  3. Reinforcement detailing: Requirements for reinforcement detailing, including cover, spacing, and anchorage.

Note: These factors differ from Eurocode (e.g., EC2 uses 1.35 G and 1.5 Q).

2.2 Materials Specification (Clause 5 of Part 4)

Concrete grades are defined by characteristic cube strength at 28 days (( f_cu )):

Part 4: Code of Practice for Design of Concrete Bridges – The core document for structural concrete calculations.

Many modern designers find Eurocode’s rotation capacity rules more complex but more accurate.

  • C40 (40 N/mm²): Minimum for reinforced concrete superstructures.
  • C50 (50 N/mm²): Common for prestressed concrete beams.
  • C60+ (60 N/mm²): Used for high-performance, durability-critical zones.