Experiences from the Five-Year Monitoring of a Long-Span Pontoon Bridge: What Went Right, What Went Wrong and What’s Next?

Abstract

The Bergsøysund Bridge is a 930-metre-long end-supported pontoon bridge located in Norway, and has been the target of a five-year-long, extensive monitoring program. Herein, we will describe the unique structural characteristics of the bridge. The monitoring system has been under continuous expansion and revision, and consists of sensors monitoring both the excitation and the response of the bridge. Quantification of the uncertainties of the modelling methodology for structures of this nature has been the main goal, for which purpose modal analysis has been an indispensable tool. Modal analysis has also been used to study the effects the environment has on the structure's dynamic behaviour. We discuss the limitations of the results from modal analyses. Furthermore, we rise the question of how long monitoring campaigns may continue to provide useful information of this bridge and similar civil structures.