Dynamic Tests on Large Cable-Stayed Bridge

Abstract

This paper describes the dynamic tests performed on a large cable-stayed bridge, Vasco da Gama Bridge, on the basis of a nonconventional testing system, comprehending several independent accelerographs conveniently synchronized by a laptop, as well as a laser interferometry system for noncontact dynamic measurements in stay cables. This system showed to be rather portable, efficient, and accurate, leading to the creation of a very large high quality database concerning the dynamic behavior of the bridge. Subsequent processing of the data permitted accurate identification of all the significant modal parameters of interest from the aerodynamic and seismic point of view and presented a very good correlation with the corresponding values provided by the 3D numerical finite-element model previously developed at the design stage.