Bridge Monitoring

Maintaining and monitoring of bridges is of great economic importance in order to avoid damages and the attendant traffic limitations. In civil engineering reliable monitoring of the building stock and early detection of damages serve as guiding principles for future research.

Our concept of monitoring bridges combines on-site inspections of the building by statical and/or dynamic measurements with Finite-Element calculations and remeasurements at specific times. Typically we conduct a detailed basic measurement to determine the modal parameters and static properties of the bridge. The optimisation process is used to calibrate a FE- model representing the realistic dynamic behaviour. These surveys show that it is already possible to evaluate the bridge condition and to calculate realistic reliability indices based on vibration measurements.

In principle it is possible to operate bridge monitoring systems on a periodic or continuous base:

• Periodical testing: measuring the vibration behaviour is carried out in specific time intervals. Sensor location should be in accordance with the initial measurement.
• Continuous monitoring: sensors are installed permanently to the bridge, providing a continuous data concerning bridge condition.