Dynamic Weighing Through Vibration-Based Structural Monitoring in a Prestressed Concrete Road Bridge

Resumen

The aim of this study was to implement a vibration-based approach for non-invasive dynamic weighing of a deteriorated prestressed concrete bridge. The research is set within the current context of road infrastructure, which is increasingly impacted by the frequent passage of overloaded vehicles. The proposed methodology relies on the structural vibration response recorded by a monitoring system composed of accelerometers and strain gauges mounted directly on the bridge girders. While commercial Bridge Weigh-In-Motion (B-WIM) systems have demonstrated high accuracy in estimating Gross Vehicle Weight (GVW), their implementation is often constrained by the ideal structural conditions required for proper operation. Moreover, these systems rely primarily on strain measurements, which require more complex and costly instrumentation, particularly in long-span bridges. In contrast, the proposed methodology is based on vibration measurements, which can be obtained using more portable equipment that cover larger areas with fewer sensors. Through numerical simulations and experimental validation, the method achieved high accuracy in estimating both GVW (with errors below 5%) and axle weights (with errors below 10%). The results demonstrate that this methodology is an efficient tool for roadway load monitoring, contributing to the reduction of structural risks and the improvement of road infrastructure management.