To examine the reliability of existing structures, environmental and traffic situations leading to extreme effects, have to be considered. For instance, in the case of given bridges, it is necessary to take into account the influence of wind, as well as its combination with extreme effects due to traffic.

As a part of the European project INFRASTAR, research in this area is carried out on the Millau viaduct (France). In the recent study, two months of Weigh-In-Motion (WIM) data have been used for evaluation of effects from traffic. Effects caused by the wind have been obtained from values measured at the highest level of bridge towers by Supervisory Control And Data Acquisition (SCADA) systems. Methodic studied by Zhou (2013) is used for statistical analysis of traffic loads; wind effects are applied according to Zhang et al (2014) and Arena et al (2014).

Results include responses of the bridge to combinations of the worst case of vehicles position with extreme values of the wind at the most unfavorable direction. The main objective of this paper is an observation of the influence of the wind on the bridge behavior under traffic loading for the future prediction of extreme load cases and estimation of a safety level of structures.