Comparison of full-scale measurement and computation of wind effects on a cable-stayed bridge

Abstract

This paper compares full-scale measurements of wind-induced acceleration of the Saint-Nazaire cable-stayed bridge with quasi-steady aerodynamic approach. The full scale turbulence was measured on the deck (three components on four masts), as well as the structural damping of vertical modes and natural frequencies. Other dynamic characteristics of the bridge were obtained by usual modal analysis and steady aerodynamic coefficients by section model tests. Comparisons have shown a satisfactory level of accuracy of the quasi-steady theory in predicting aerodynamic damping. This theory, assuming aerodynamic admittance equal to unity, is conservative, as a rule, but it is not in the particular case of the vertical mode of the Saint-Nazaire bridge.