FINITE-ELEMENT MODEL UPDATING FOR THE KAP SHUI MUN CABLE.pdf

FINITE-ELEMENT MODEL UPDATING FOR THE KAP SHUI MUN CABLE-STAYED BRIDGE By Q. W. Zhang,1 T. Y. P. Chang,2 and C. C. Chang3 ABSTRACT: This paper presents the implementation of the finite-element model updating for the Kap Shui Mun Bridge, a 430 m main span double-deck cable-stayed bridge in Hong Kong. The dynamic characteristics of the bridge have been studied through both three-dimensional finite-element prediction and field vibration measurement previously. In this paper, the developed finite-element model is updated based on the field measured dynamic properties. A comprehensive sensitivity study to demonstrate the effects of various structural parameters (including the connections and boundary conditions) on the modes of concern is first performed, according to which a set of structural parameters are then selected for adjustment. The finite-element model is updated in an iterative fashion so as to minimize the differences between the predicted and the measured natural frequencies. The final updated finite-element model for the Kap Shui Mun Bridge is able to produce natural frequencies in good agreement with the measured ones, and can be helpful for a more precise dynamic response prediction. INTRODUCTION nite-element model. The finite-element results and the field vibration test show reasonable correlation in terms of the nat- The Kap Shui Mun Bridge (Fig. 1), located between the ural frequencies and the mo