The main objective of field measurements on railway bridges is to collect crucial information in order to improve the service life estimation of existing infrastructure.

The measured data is used to estimate both the the axke loads of the trains and the stresses felt by the structure.

Another goal is to quantify numeric model errors and also improve numerical models by validation and model updating. To achieve this, a measurement system has been designed with the following specifications:

• 20 triaxial accelerometers
• 40 channels for strain measurements
• RTD temperature measurements
• GPS clock for synchronization with other measurement systems
• Network capability for remote control and storage of data

The system is being installed on Stjørdalselva railway bridge in the second quarter of 2016. To make things a bit more interesting, the bridge lies just a few hundred meters from Hell railwaystation, the construction is a pony truss riveted steel bridge from 1902 with five spans at 35m.