Precast, Prestressed Pedestrian Bridge World's First Reactive Powder Concrete Structure

Spanning 197 ft (60 m), this precast, prestressed pedestrian/bikeway bridge in Sherbrooke, Quebec, is a post-tensioned open-web space truss containing no conventional steel reinforcement. Made up of six prefabricated match-cast segments, it was manufactured using Reactive Powder Concrete (RPC), a cement based material proportioned with sand, cement, and powders of silica fume (microsilica), and quartz, with fine steel fibers added to enhance ductility. In the top and bottom chord member, the RPC has a compressive strength of 29,000 psi (200 MPa). For the web member diagonals, RPC was confined in stainless steel tubes, attaining improved ductility and a compressive strength of 50,000 psi (350 MPa). An extensive program monitoring bridge deflections and forces in the prestressing tendons has been implemented to provide information on long-term performance of RPC.