PIV investigation of flow around submerged river bridge deck

摘要

The flow field around a submerged bridge deck has been experimentally investigated here. The deck submersion may be a critical situation for structural stability of river bridges. This problem has been not sufficiently discussed in the past. In order to clarify some aspects of the hydrodynamic loading mechanism, we have kinematically studied the characteristics of the large-scale vortexes in the bridge wake by an original PIV technique. The bridge deck has been modeled by means of a rectangular cylinder. Mean and time-averaged velocity fields have been studied for low submergence ratios of the bridge deck. The work has provided some interesting results. The flow fields around the deck had shown a strong asymmetry and a complex vortex shedding regime, the analysis of which has allowed us to highlight the main differences from symmetrical unbounded case and to associate the considered kinematic behavior to the corresponding dynamic reaction.