A SIMPLE APPARATUS FOR MEASURING SELF-EXCITED WIND FORCES ON BRIDGES

A simple vibration system consist of stepping motors and force transducers was designed and fabricated to measure the self excited wind loads acting on bridge sections. The bridge section model installed on the system was harmonically excited either vertical or torsional at a time. Then the measured forces were converted to the flutter derivatives by applying the Fourier and Hilbert transform. From the wind tunnel tests, the effects of the frequencies, amplitudes and angles of attack on flutter derivatives were investigated. Moreover the flutter derivatives for six bridge sections were provided.