Abstract
The tension of the main cables in a suspension bridge is influencing critically the stiffness of the whole structural system and can be indirectly measured through the survey of its configuration. Since previously published shape-finding analysis methods or results are mostly based on the idealized structural system adopted during design, need is to pay particular attention on the exploitation of field-measured data when establishing or updating the analysis model for maintenance purpose of the bridge in service. This study intends to propose an analytic model for an actual 3-span suspension bridge with main span of 500m using the measurement resulting from its configuration survey. Based on the shape-finding analysis results relative to the dead loads, a linearized finite displacement FE model is proposed and, an attempt to extend the measurement-based shape-finding analysis method from conventional methods by reflecting progressively the measured configuration and temperature is presented. Analysis results reveal that the current configuration of the bridge in service corresponds fairly with the target configuration. This study proposes a model updating method which could provide theoretical basis for the establishment of analysis model for suspension bridges based on various maintenance data.