Libarot® – a second life for unrecovered waste seashell
Libarot® is a low-carbon binder for road infrastructure, made using crushed scallop shells. It is designed for structural maintenance of road surfaces under all traffic conditions, and is produced and applied using in-place recycling technique. This project, launched jointly in 2023 by Eiffage Route and Builders École d’ingénieurs, is supported by the Normandy and Île‑de‑France regions with additional support from Ademe under the Vallée de la Seine 2015–2022 management plan project. This innovation uses crushed scallop shells in the hydraulic binder, deriving economic and environmental benefits from this waste material. Its carbon footprint is four times smaller than with conventional binders, enabling project managers to contribute to national decarbonisation and circular economy commitments across the road network. The solution was trialled on 18 March 2025 at Eiffage Route’s Monthyon Enrobés site in north-central France.
Diamanti – a sustainable, high-performance 3D concrete footbridge
Developed by Carsey 3D, Sika, Ævia (a subsidiary of Eiffage Génie Civil) and Cerib, Diamanti is a footbridge with a 10 to 25-metre span made entirely from post-stressed 3D printed concrete. The structure boasts superior mechanical performance, allowing it to support heavy loads. Its architectural design featuring biomorphic shapes, its extremely short construction time and its minimal environmental impact make this a fascinating innovation. Material is optimally arranged within the structure to significantly reduce the quantities required. This is made possible by a new geometric structural design method that optimises the quantity of concrete used, significantly reduces the need for steel reinforcement and entirely eliminates the use of formwork. This solution also eliminates corrosion problems affecting the passive reinforcements by using prestressed cables with protective coatings.
“Routes et Rues” is an annual innovation scheme organised by the French Ministry for Regional Planning and Decentralisation.
Established by the Ministry for Regional Planning and Decentralisation in association with IDRRIM and Cerema, and co-certified by AIT (the French Agency for Innovation in Transport), the “Routes et Rues” call for projects promotes the creation of innovative technical solutions that meet the needs of road construction contractors having to adapt transport infrastructure to climate change.
The innovations recognised this year have been certified by the infra2050 competitiveness cluster. They will be the focus of experiments by public contractors keen to test them in their regions. The implemented solutions will be monitored for three years by experts from Cerema, Gustave Eiffel University and CETU (Centre for Tunnel Studies) to verify their performance and durability.
Since this innovation scheme began, Eiffage has been recognised for 20 innovative solutions: Recyclean® and R6Pont in 2015; Aéroprène® in 2016; Recytal-ARM® and Luciole® in 2017; Microphone®Stéréo and Guid’N Grip® in 2018; LuminoKrom®Vision+, Biophalt®, Skinway® and PRFC in 2019; Bioklair® (formerly BioKrom®) and Flexocim® (formerly Bio-Ertalh®) in 2020; TramERS GB5®, ÉcOasis® and HPE in 2021; Orra® in 2022; Carbon Light in 2023; and ICCAR and Actigreen® in 2024.
