ABSTRACT
This study aims to investigate the impact factor of a seven span continuous cable-stayed bridge planned for the extension of an expressway by means of a three-dimensional vehicle-bridge coupled vibration analysis. The validity of the three-dimensional analysis was verified comparing the vibration response of a single span steel cable-stayed bridge in service subjected to vehicle running tests with those numerical responses from the three-dimensional analysis. The impact factors of a seven span continuous cable-stayed bridge were found to be less than 1.07 for the main girder, less than 1.03 for the base of the main tower and less than 1.04 for the cable. The impact factor was highest when several vehicles were running at resonant headway.
