FINITE ELEMENT MODEL UPDATING OF A FOOTBRIDGE BASED ON STATIC AND DYNAMIC MEASUREMENTS

The Palmas Altas footbridge is a recently built bridge in Sevilla (Spain) designed by architect Richard Rogers.It is a 78.6m long steel-concrete box girder.The bridge has three spans, with two pairs of intermediate oblique piers.The cross section of the box girder and the piers are variable along the bridge length.The footbridge has a cylindrical roof with a complex structural geometry, made of elliptical crossing bars and a cylindrical shell.Before being taken in use, the structural response of the footbridge was experimentally identified by an operational modal analysis.Mode shapes and frequencies have been clearly identified.In addition, the static response of the structure was obtained from a static load test.A detailed finite element model has been built for analyzing both the static as well as dynamic behavior of the bridge.A model updating process has been performed to improve static and dynamic response predictions.The present analysis is mainly focused on the in plane behavior of the bridge, for which both static and dynamic experimental information is available.Special attention is paid to the role of the bearings and foundations in the structural response.It is shown that the measured static response provides useful information about the response of the bridge and its foundation, which is not available from a dynamic analysis only.