Proof Loading Test Under Controlled Exceptional Vehicle Passages: A Case Study

In recent years, Structural Health Monitoring (SHM) has become an essential tool to ensure the safety and reliability of existing bridges. This study focuses on a prestressed concrete multi-span bridge in northern Italy, aiming to develop and calibrate a highfidelity finite element (FE) model using experimental monitoring data. The bridge was subjected to an extensive inspection campaign and to controlled crossing of heavy vehicles, during which dynamic response and deflections were recorded. An iterative calibration scheme was implemented to update the elastic properties of the structural components, minimizing the discrepancy between measured and numerical modal parameters. The calibrated model showed excellent agreement with the experimental natural frequencies and a satisfactory correlation with measured deflections under moving loads. The results demonstrate the reliability of the calibrated FE model and its suitability for future simulations under different traffic and potential damage scenarios, supporting bridge maintenance and safety assessment.