Salini Impregilo (Webuild): Pioneer of Innovative Building Techniques

PUBLI-RÉDACTIONNEL

With its return to France, Italy’s Salini Impregilo (recently renamed Webuild with the acquisition of Italian peer Astaldi) brings a pioneering spirit to the application of the latest innovative techniques to major infrastructure projects. On a section of the tunnel being excavated for Line 14 South (L14-GC04) as part of the expansion of the network managed by the Régie Autonome des Transports Parisiens (RATP), it is using carbon-fibre strips rather than the traditional steel ribs – a first in France.

With a combined track record of more As the tunnel-boring machine (TBM) than 13,637 kilometres of rail and grinds forward, a team of three to four metro lines over a span of 114 years, workers use a layer of epoxy mortar to Webuild, which has come to include apply two strips to each ring formed Italy’s Astaldi, is a major contribu- by precast concrete segments installed tor to the development of urban and by the TBM. Each strip is composed of extra-urban mobility, supporting efforts four sections. As they are applied, the to reduce traffic and pollution by offe- sections overlap each other for about ring safe, efficient and environmentally 800 millimetres. Each strip measures friendly public transport services. Its about 4.5 metres in length. That leads projects not only help economic growth to the two strips covering about two- Extension of Line 14 south to Orly Airport and job creation, but also lend support thirds of the circumference of the tun- within Grand Paris Express Project (Lot 4) to cities and regions in reaching sustai- nel in order to leave the floor free for Carbon fibers plates - General view of the nable development targets set by the passage. tunnel United Nations. Line 14 South, as well as Line 16 on The tubes, cables and ventilation sys- which Webuild is working for the Grand tems already mounted along the inner Paris Express, mark the Group’s return walls would have had to be taken down, to France after more than 20 years. forcing the TBM to halt operations tem- Between 1992 and 1998, it worked on porarily. This would have resulted in the Paris rail lines Est-Ouest Liaison Express loss of precious production time. The (EOLE) and METEOR (Metro Est-Ouest use of carbon-fibre strips, meanwhile, Rapide). has saved months of time – an -enor The carbon-fibre strips that it is applying mous benefit. Workers can put the on Line 14 South are for the inner walls strips in place by hand behind the tubes, of the 120-metre-long section of the cables and ventilation systems without tunnel that passes through the site of having to take everything down. the future underground station of Paris Webuild’s expertise in developing metro Orly Airport. The strips hold the walls in systems is also on display elsewhere place before the section is demolished in the world. In Copenhagen, it com- as the earth around it is excavated to pleted Cityringen. In Milan, it is fini- create the box for the station. shing the excavation of the tunnels for It is the first time in France that the the M4 line, while in the Middle East, Extension of Line 14 south to Orly Airport strips are being used for this purpose. it worked on Line 3 in Riyadh and the within Grand Paris Express Project (Lot 4) In most cases, they act as a permanent Carbon fibers plates - Detail of monitoring Red Line North Underground in Doha. reinforcement of a tunnel. gauges It is also a leader in light rail transit. In Webuild is using the strips rather than Perth, for example, it is completing the traditional steel ribs because they are The original plan was to install Forrestfield-Airport Link. ■ thinner, lighter, more flexible and easier 86 HEB steel profile ribs at intervals to install. Indeed: the strips are about of 1.8 metres along the section of the 15 centimetres wide and 1.2 milli- tunnel to be demolished. But it would metres thick. have been much more cumbersome. Photo: Stéphane Bouquet Stéphane Photo:

Webuild est fier de contribuer au développement du Grand Paris Express sur les lignes 16 et 14 Sud.

Nous sommes Webuild, le nouveau groupe Nos projets de transport souterrain né en 2020 de Salini Impregilo, leader mondial dans en construction déplaceront 3 millions la construction de grands projets d’infrastructure de personnes chaque jour, réduisant pour la mobilité durable, l’énergie hydraulique, de 550 000 tonnes d’émission de CO2 par an. l’eau propre et les bâtiments verts.

13 637 km de voies ferrées et métro 2 373 km de tunnels