Bridge for seamless connect

Two of PASCHAL’s regular customers are both working on the extension of the tram line to the station in Kehl. EIFFAGE CONSTRUCTION is responsible for ‘Extension East Tramline D’ and has opted to rent the LOGO.3 formwork system. The section of this construction project known as ‘Pont Citadelle’, involving two bridge foundations and two abutments, is in the hands of GTM-HALLE. This company is renting LOGO.3 and the Modular formwork system.

According to reports, extension of tram line D is important for Strasbourg because the route borders on large and significant areas of development land – directly beside the tram stop ‘Aristide Briand’ a new residential area will be built. The animal home opposite is to be relocated and this will free up a large plot of land measuring several hectares. At the present time, nine hectares are lying fallow in the ‘Vauban Basin’ and are now ready for construction work to begin.

Against this backdrop, the city authorities envisage the tram serving a catchment area with a population of more than 20,000 including residents, employees and school pupils. The tram line is to be routed down the existing Route du Rhin, which means that two bridges will need to be constructed. The first bridge will span the Vauban Basin. Here, GTM-HALLE is using formwork systems from PASCHAL to construct two bridge foundations and two abutments to absorb the forces applied by the diagonal curved section of track.

On this section of track, extending over a distance of 2.6 kilometres, five tram stops are planned: The first after 520 metres near the existing Vauban bus stop and the second near the Desaix rail bridge. When this rail bridge was upgraded to handle TGV/ICE trains (high-speed trains) the width of the bridge span was increased to such an extent that the tram line can be routed underneath it. The third of the five stations is adjacent to Rue Coulaux, the fourth is on the former site of the French customs border post shortly before the Europe Bridge, while the fifth will be located on the forecourt of the railway station in Kehl.

‘Extension East Tramline D’
To lower the height of the tramline, a comprehensive range of underground construction and structural engineering services is required which is being provided by EIFFAGE CONSTRUCTION. This section of construction work is being managed by Dipl.-Ing. Oliver Stutzmann, the site manager responsible here.

To resolve all of the formwork-related tasks, the construction company performing the work has elected to rent just one formwork system, LOGO.3, from PASCHAL. Even the two oval arch piers were made of fair-faced concrete using LOGO.3 formwork and box-outs by site. The requirement for using just SIX tie points was satisfied through close collaboration between the production planning team at PASCHAL and the construction site team in charge.

To set up formwork on the foundations to the left and right of this lowered section of track, roughly 107 sq.m of LOGO.3 formwork was used. Concreting the abutments involved the use of about 140 sq.m of formwork from PASCHAL, while half was covered by an additional plywood layer for the fair-faced concrete.

With the help of the formwork planning specialists from PASCHAL, the requirements were met for a uniform joint pattern to be achieved over the entire length of about 116 metres, at one point with a downhill gradient of 2.3 degree and at another point with an uphill gradient of 2.3 degree to create an ‘underpass’. This involved the section being sub-divided into seven separate concreting phases.

The photo shows the prepared LOGO.3, laid double up to the lower edge of the completed concrete abutment.

Fair-faced concrete wall with a protective function
Once concreting work was completed on the abutment for the TGV/ICE line on the sunken piles, and after the concrete had set firmly, LOGO.3 formwork was installed for a wall of fair-faced concrete extending over a length of 40 metres at the height of the tram line to clad and protect the piles between abutment and the lower leading edge of the concrete structure.

Single-sided formwork over a 40-metre length for self-compacting concrete
In order to concrete a total of 240 sq.m of concrete walls under the completed abutment, 64 sq.m of LOGO.3 formwork was mounted with an additional layer and fitted with a filling nozzle to pour in the self-compacting concrete.

In 7 phases, each over a total length of about 22.70 metres on the south side, a concrete wall measuring 158 metres in length was built with the help of double laid formwork. On the north side, again over a length of 158 metres, a wall of fair-faced concrete was constructed with LOGO.3 formwork but without additional plywood layer.

Cutting excavation
To excavate this cutting, extending over a surface area of about 58 sq.m, after the base plate had been concreted, the lower section of the wall was formed using single-sided LOGO.3 formwork. Then the retaining walls were raised further. Double-sided LOGO.3 formwork was used for this.

After completion, steel sheeting will span the entire lowered section of tram lines, supported by the oval steel-reinforced concrete piers. In total two steel-reinforced concrete columns in fair-faced concrete were built with LOGO.3, using only 6 tie points.

‘Pont Citadelle’, two bridge foundations, and two abutments
The intention is to route tram line D over the Vauban Basin in the direction of Kehl over acurved steel bridge section 160 metres in length, starting at its current terminus, the ‘Aristide Briand’ tram stop. For the two bridge foundations and for the two abutments, the construction company involved, GTM-HALLE, is renting from PASCHAL its two formwork systems, LOGO.3 and the Modular formwork system. Forming the abutments and bridge supports involved the use of about 170 sq.m of LOGO.3 formwork. Only 63 sq.m of formwork were enough to build the foundations.

14