Simplified site-specific traffic load models for bridge assessment

Traffic load is identified as one of the greatest sources of uncertainty in the assessment of bridges. In recent years, simulation techniques, using measured traffic data, have been used to predict the characteristic traffic load effects on bridges. However, the techniques are complex, sensitive to the assumptions adopted and require specialist statistical expertise. This work presents a simplified site-specific traffic load model that generates comparable load effects to the corresponding results from a full simulation. While the simplified model is still sensitive to the underlying assumptions, these can be carefully reviewed prior to the method being approved. Further, the simplified method can be employed by practising engineers for bridge assessment.