International Experiences

New thin UHPC deck for the "Grand Pont" of Thouaré-sur-Loire — How to extend serviceability of a 19th century steel through truss bridge?

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Abstract

The “Grand Pont” of Thouaré-sur-Loire is a 430 yards long steel through-truss bridge crossing the Loire river in Nantes area (France) bearing an increasing commuting traffic of 10 500 vehicles a day. The structure was suffering significant pathologies related mainly to waterproofing failure that could have led to the collapse of the brick masonry arches supporting the structure or to a steel floor beam breakage. The operation of rehabilitation and improvement of the level of service of the “Grand Pont” of Thouaré-sur-Loire involved among others the complex realization of a new integral UHPC deck. This very thin deck, made up of UHPC prefabricated slabs, connected on site with UHPC joints, allowed to relieve the bridge of half of the deck dead weight. The gain in thickness also enabled to reinforce the 135-year-old steel structure, which has been completely conserved, by superimposing new metallic beams without changing the finished level of the roadway. The implementation of this construction technique allowed to drastically reducing the completion time of the project and traffic interruption.

Keywords: steel through-truss bridge, UHPC deck, prefabricated slabs, UHPC connections, completion time

How to Cite:

Roux, G., Jaffrelo, S. & Dupeyroux, T., (2019) “New thin UHPC deck for the "Grand Pont" of Thouaré-sur-Loire — How to extend serviceability of a 19th century steel through truss bridge?”, International Interactive Symposium on Ultra-High Performance Concrete 2(1). doi: https://doi.org/10.21838/uhpc.9639