Research on the application of high-frequency base balance in wind tunnel test

High-frequent base balance (HFBB) was applied for the test of the three-component aerodynamic force coefficients of one streamlined bridge deck section model. Frequency spectrum analysis and digital filtering was performed for removing the inertia force caused by the vibration of the model system, by which the measurement accuracy can be improved. The torsional center eccentricity resulting from eccentric model mounting influence on torsional moment coefficient was studied. The research indicates that inertia force effect can be regarded as white noise basically, which has almost none effect on the average of the aerodynamic force, whereas it magnified the standard deviation, so the rigidity of the model should be guaranteed. The effect of vertical eccentric torsion is so small that there is no need to calculate. Nonetheless, the lateral eccentric torsion has obvious effect, which cannot be ignored. Hence, the lateral eccentricity should be minimized.