Halskestrasse is currently being upgraded for the creation of cycle route 9. A new pedestrian and cyclist bridge – a network arch bridge – has been built as part of this route. To ensure that the loads on the bridge are transferred according to the structural design, the suspenders are prestressed with high forces during construction.

Our task:

After the bridge had been completed, we were asked to check if the prestressing forces in the suspenders correspond to the design forces or if any elements experience excessive stress.

We carried out frequency analysis to determine the stress in the suspenders. One sensor was attached to each suspender to measure the eigenfrequencies. Using this information, we were able to calculate the forces present in the cables.

The results were used to adjust the prestressing forces before the bridge was moved into its final position.