Full-scale monitored wind and response characteristics of a suspension bridge compared with wind tunnel investigations at the design stage

Structural health monitoring of long-span bridges makes it possible to assess the assumptions and considerations in the design stage of the structures through measurements of their structural response and environmental conditions. In wind-resistant design of long-span bridges, the wind-induced dynamic buffeting response is difficult to assess as the uncertainty in the loading and the structural and aerodynamic characteristics is high. In that case, one of the best sources of information is wind tunnel tests, in addition to field measurements and analytical considerations. However, it is unclear if such methods can provide reliable information for the designer since, typically, many uncertainties and assumptions are involved in such a process. Here, we evaluate the scaled full aeroelastic and terrain model tests carried out during the design stage of the Gjemnessund Bridge in Norway through comparisons with full-scale monitoring data spanning five years. The monitoring system and the data are presented along with the wind tunnel study. The results from both campaigns are analyzed and critically discussed, emphasizing implications for the wind-resistant design of long-span bridges.