Dynamic Assessment of Curved Cable-Stayed Bridge by Model Updating

Bridges are indispensable components of the infrastructure of modern society, and their assessment via techniques of structural dynamics is assuming greater importance. This assessment concerns performance of the as-built structure compared to the design and can also extend to the assessment of structural deterioration or damage. Simple validation of numerical results by dynamic testing has met some success; however, feedback from testing into analysis is usually crude, and only recently have systematic techniques been developed that can be supplied to such structures. This paper investigates the application of sensitivity-based model updating technology to the dynamic assessment of the Safti Link Bridge, a curved cable-stayed bridge in Singapore. Based on the measured modal data from prototype testing, the simulated dynamic properties obtained via finite-element analysis have been significantly improved by modification of uncertain structural parameters such as Young's modulus of concrete and structural geometry.