Aeroelastic effects on a rectangular box-girder bridge

Rectangular box-girders are commonly used for prestressed concrete bridges constructed by the balanced cantilever method. The aerodynamic characteristics of such a girder, with width to depth ratio varying between 1.4 and 2.9, are investigated in a series of wind tunnel tests. The aeroelastic tests carried out with a low structural damping (damping ratio 0.2% of critical) revealed the presence of vortex shedding and galloping forces both in turbulent and smooth flow. Possible description of these effects in terms of a linearized aerodynamic damping is discussed. The RMS displacement estimate associated with such a damping parameter is compared to the monitored displacement data. Lift force in the response calculation is taken into account according to Vickery's stochastic model of across-wind loading, based on the data from pressure measurement tests with a non-moving model. (C) 1998 Elsevier Science Ltd. All rights reserved.