EXPERIMENTAL INVESTIGATIONS ON VORTEX SHEDDING EXCITATIONS OF FLAT BOX BRIDGE SECTIONS

In connection with flexible long spanned bridge structures it is called for to disclose the vortexshedding excitations of flat box type cross sections which commonly are induced in rather lowwind velocity.In this paper an attention is particularly placed on three themes, namely (I) the effect of pitchingangle, (ii) the effect of turbulence incident to natural strong winds and (iii) consequent treatmentfor improvement of aerodynamic stability. In addition to these the effect of solidity ratio of trussgirders on vortex induced excitations is also discussed based on the wind tunnel tests.In connection with flexible long spanned bridge structures it is called for to disclose the vortexshedding excitations of flat box type cross sections which commonly are induced in rather lowwind velocity.In this paper an attention is particularly placed on three themes, namely (I) the effect of pitchingangle, (ii) the effect of turbulence incident to natural strong winds and (iii) consequent treatmentfor improvement of aerodynamic stability. In addition to these the effect of solidity ratio of trussgirders on vortex induced excitations is also discussed based on the wind tunnel tests