BS 5400 Part 2 specifies the loads to be considered in the design of steel, concrete, and composite bridges. It provides guidelines for determining nominal loads, applying partial safety factors, and forming load combinations in accordance with limit state design principles.
🔹 Scope
- Applicable to highway, railway, pedestrian, and cycle track bridges.
- Defines load values and combinations for both ultimate and serviceability limit states.
🔹 Types of Loads
- Permanent Loads
- Dead load (self-weight of structural components)
- Superimposed dead load (wearing course, parapets, utilities, etc.)
- Transient (Variable) Loads
- Traffic live loads
- Pedestrian loads
- Wind loads (vertical and horizontal)
- Temperature effects (expansion and contraction)
- Earth pressure and settlement effects
- Construction and erection loads
- Highway Live Loading
- HA Loading – Represents normal traffic using distributed and concentrated loads.
- HB Loading – Represents abnormal heavy vehicles for special design checks.
🔹 Load Combinations
The code specifies different load combinations to check structural safety (ultimate limit state) and serviceability (deflection, cracking, vibration).