Publication
As many bridges are approaching the end of their supposedly theoretical service duration, finding novel technical solutions to extend their service duration is crucial, also for reasons of sustainability. In this article, two strategies (structural performance monitoring, and strengthening with ultra-high-performance fiber-reinforced cementitious composite (UHPFRC)) are introduced to avoid prematurely replacing structures. The case study of the Ferpècle road bridge (Valais, Switzerland) is presented since the two strategies were combined in 2023 to extend its service duration. This bridge is one of the first prestressed concrete bridges in Switzerland. Built in 1958, the structure consists of a single girder with a 34.5-meter span resting on abutments in the form of reinforced concrete piers. As the deck has a width of only 5.3 meters, bridge owners have decided to widen it to 7.9 meters in order to include two road lanes and a pedestrian way. Despite its good condition, the bridge must be strengthened as its load-bearing capacity (bending moment at mid-span) would be largely insufficient with the new deck width. To increase its load-bearing capacity while widening the bridge deck by 50%, an intervention with UHPFRC has been made. The innovative intervention enables clamping the abutments with the bridge deck to modify the static system to obtain a semi-rigid frame to reduce the bending moment at midspan. Two load tests using the latest sensing technologies, before and after the intervention, have enabled the quantification of the design capacity and the validation of this pioneering intervention. This case study demonstrates the potential of novel technologies to extend bridge service duration, thereby improving the sustainability of the construction sector.