UHPFRC prestressed beams as an alternative to composite steel-concrete decks: The example of Pinel Bridge (France)

This paper describes the design and construction of the third Pinel Bridge in France, in 2007. Located just to the west of Rouen, this small bridge has a single 27-m-long span and is 14-m wide. It will increase the traffic capacity of two existing bridges over three railroad tracks from two lanes to five. The bridge deck combines a conventional slab of standard reinforced concrete with seventeen parallel contiguous beams made of self-consolidating Ultra-High-Performance Fiber-Reinforced-Concrete (UHPFRC). The beams – designed by the contractor, Eiffage TP, as an alternative to a filler-beam deck – are prestressed with 28 internal strands placed in a very wide bottom flange 1 GENERAL DESCRIPTION OF THE BRIDGE Located in Le Petit Quevilly, just outside Rouen, Pinel Bridge is used by vehicles travelling between the south-bank expressway and roads serving Rouen Harbor. It is 27-m-long, has a high skew angle, and crosses three railroad tracks serving a marshalling yard (see figure 1). The original single-lane bridge built during the 1970s was duplicated in 1996. These two bridges have concrete substructure units on shallow foundations and carry two lanes on parallel filler-beam decks connected only by a longitudinal expansion joint. They have two spans of 12.20 and 14.80 m. (see figure 2). In 2008, the “La Motte” traffic circle south of Pinel Bridge will temporarily become the end of a new expressway joining the A150 motorway and southern expressway no. III via the new Gustave Flaubert vertical lift bridge (see figure 3). For this reason, the Figure 1. Bridges before triplication. local authorities decided to widen the existing Pinel Bridge from two lanes to five. This paper briefly describes the very conventional solution initially designed for the widening of this bridge, then details the design and construction of the much more innovative solution proposed by French contractor Eiffage TP. The variant solution combines UHPFRC beams, placed edge to edge, with an ordinary concrete deck slab (C35/45). This is the fifth French road bridge to incorporate UHPFRC structural components. The first four are the two bridges of Bourg-lès-Valence, south of Lyons, the Saint-Pierre-la-Cour bridge in Mayenne (western France), and Chabotte Bridge on the A51 motorway (Grenoble-Marseilles). This paper briefly describes the very conventional solution initially designed for the widening of this bridge, then details the design and construction of the much more innovative solution proposed by French contractor Eiffage TP. The variant solution combines UHPFRC beams, placed edge to edge, with an ordinary concrete deck slab (C35/45). This is the fifth French road bridge to incorporate UHPFRC structural components. The first four are the two bridges of Bourg-lès-Valence, south of Lyons, the Saint-Pierre-la-Cour bridge in Mayenne (western France), and Chabotte Bridge on the A51 motorway (Grenoble-Marseilles). 1.1 General data on the initial solution The new Pinel bridge has the following geometrical characteristics (see Figures 4 and 5): • Single span of 27 m • 14 m wide