A new 5-kilometer-long safety tunnel was built between 2020 and 2025 alongside the Kerenzerberg tunnel on Switzerland’s A3 national highway in the canton of Glarus. During construction, a temporary roadway used 2,000 prefabricated plastic-fiber-reinforced concrete slabs. To avoid landfilling these non-recyclable 4.5-ton slabs, new uses were pursued after their removal from the tunnel. This paper describes the processes to evaluate their reuse potential, through three key projects. The slabs’ condition and structural capacity were first assessed, discarding any use in bending due to the lack of continuous reinforcement. A call for projects then led to the reuse of most elements, primarily as pavement. The Walkeweg school project in Basel ultimately did not use the slabs due to a mismatch between the functional requirements of the project and the characteristics of the slabs, specifically issues of oversizing, storage limitations, and procurement constraints. In contrast, the projects Canton Zurich, which had different usage contexts and technical demands, were able to incorporate the slabs effectively: the Uster cantonal school reused 80 slabs, and the Juch-Areal recycling center reused 288. The temporary use at Uster leads to first experiences which are beneficial for the following use at Juch-Areal. The availability of free storage space also simplified logistics for this last project. A life-cycle assessment confirmed that reusing the Kerenzerberg slabs as outdoor pavement cuts CO2eq emissions by 50% compared to bituminous pavement, at competitive costs. However, the slabs’ design, intended for single use, limited reuse options. Additional anchor points for flipping and continuous steel reinforcement would have expanded their applications.
