Full Scale Measurement of Wind Pressure on a Deck of a Concrete Cable-Stayed Bridge

Part 2 Spectra of Fluctuating Pressure and Reynolds Number Effect

Abstract

Aerodynamic stability of long span bridges is usually investigated by wind tunnel tests. Due to the Reynolds number (Re) effect, however, different aerodynamic phenomena are sometimes observed between wind tunnel tests (Re: 10³-10⁵) and actual bridges (Re: 10⁶-10⁷). But there are a few studies discussing the aerodynamic phenomena in the range of 10⁶≤Re≤10⁷, because it is quite difficult to execute the full scale measurement of bridges.
In this study the Reynolds number effect on the vortex shedding frequency (i.e. Strouhal number, St) was investigated using spectrum analyses and wavelet analyses of wind pressures acting on a deck measured at IKARA OOHASHI Bridge. The results showed that the St number observed at the bridge (Re≅10⁶) were well corespondent with those observed by wind tunnel tests (10⁴≤Re≤10⁵).