Strength of steel meets beauty in design

The use of high strength steel met the architectural brief for the new bridge spanning the Moselle, linking Grevenmacher in Luxembourg and Wellen in Germany. The bridge, which was inaugurated yesterday, has been in use since October 2013.

The engineering structure had several constraints, such as the need to use strong, lightweight, custom-made materials to achieve the refined, streamlined design, not to mention a very tight, four-and-a-half month construction schedule to minimise traffic disruption. Mission accomplished for Poncin, the company responsible for the project’s steel infrastructure,with ArcelorMittal supplying tailor-made plates for the construction of key bridge arch components, exploiting the full rolling capabilities of the ArcelorMittal Gijón mill in Spain.

A spectacular high-profile project

Poncin and ArcelorMittal have a longstanding partnership based on trust, but the ability to deliver a quality result on time was crucial in winning the contract for this high-profile project because it presented an aesthetic challenge that spanned two countries and had to be completed speedily. “We needed reliable contractors, steelmakers capable of supplying custom-made products quickly,” explains Benoît Comblin, Poncin’s project engineer. “Despite the distance between the construction site and the workshops, the excellent service from ArcelorMittal’s Gijón plant in Spain helped keep us bang on schedule.”

Complete rebuild in four and a half months

The old Grevenmacher bridge was built from prestressed concrete back in the 1950s, so the Luxembourg authorities decided it was time to replace it. For safety reasons, increased traffic on the bridge with some 17,000 vehicles crossing daily meant that it had to be entirely rebuilt. The old structure was demolished to make way for a 213 metre-long orthotropic deck bridge with four spans. One of the characteristics of the new structure is the absence of piers in the river to ensure the widest possible navigable clearance; the use of steel made this possible.

The ArcelorMittal steel for the project had to be delivered within a very short and specific time frame and the Gijón teams were right on schedule. In January 2013 Poncin began to construct the steel frame of the bridge, which was assembled in the port of Mertert in March. While work was being completed on the central span stretching 113 metres from shore to shore,the old bridge was demolished during the annual lock closure, from 4 to 11 June. The deck elements linking the ground level with the aerial section were transported by lighter barge then brought into position using jacks. The materials for the bridge were custom made.

“We hardly used any rolled sections,” explains Benoît Comblin. In keeping with new architectural trends Nicolas Dujardin, Account Manager ArcelorMittal, comments: “This trend towards using high strength steel grades to build engineering structures offers designers two advantages: lightness and elegance.”