Installation of the first Exegy® ultra-low-carbon segment on the Grand Paris Express worksite

Credit: Yves Chanoit

2 June 2022 - Events - France

Line 18 of the Grand Paris Express has received the first segment made of Exegy® ultra-low-carbon concrete, VINCI Construction's low-carbon concrete range.

Until now, the segments used in the tunnels on the site had already been very low-carbon (composed of 60% slag, a residual material from blast furnaces that can be substituted for cement). In partnership with Ecocem, VINCI Construction developed ultra-low-carbon Exegy® concrete, in which the cement is entirely replaced by the alkali-activated binder Ecocem Ultra. This avoids approximately one tonne of CO₂ per metre of tunnel, a reduction of more than 50% compared with the concretes currently used. In total, four complete ultra-low-carbon rings will be installed by 2023, i.e., almost thirty segments.