Post-rehabilitation assessment of a centenary steel bridge through numerical and experimental analysis

Abstract

This paper presents an experimental and numerical analysis regarding the structural assessment of an existing steel bridge – the Eiffel Bridge – after a recent rehabilitation. The Eiffel Bridge, a centenary road–rail truss bridge, comprising two superimposed decks, was subjected to major rehabilitation works involving the replacement of the top concrete deck, the strengthening of the upper chords of the main truss girders and the replacement of the support bearings. In this context a load test and an environmental test were carried out aiming at the assessment of the new structural condition and the evaluation of the effectiveness of the elements' strengthening. A structural analysis was carried out in order to characterize the most relevant aspects of the structural behavior and to support the discussion of the field results. Particular aspects concerning the main girders' bending, the nature of nodes' rotations, and the response under temperature changes are highlighted. The effectiveness of the strengthening of the top chords is verified based on the strains' measurements. Finally, it is shown that the thorough characterization of the structural behavior enabled the establishment of a reference condition for future assessments of the structure.