Behavior of CFCC and CFRP Leadline Prestressing Systems in Bridge Construction

Abstract

Two commercially available carbon fiber reinforced polymer (CFRP) prestressing systems were compared for use in continuous prestressed concrete bridges in this investigation. Two two-span double-tee (DT) continuous bridge models were fabricated, instrumented, and tested. The two bridge models were identical except that Bridge Model CDT1 was pretensioned and post-tensioned with the CFRP Leadline tendon system, whereas the carbon fiber composite cable (CFCC) system was used in Bridge Model CDT2. The study examined parameters such as midspan deflections, concrete strains, and post-tensioning forces in externally draped strands/tendons under static loading and 15 million cycles of repeated loads. The ductility, failure modes, load carrying capacities, and post-tensioning tendon forces of both bridge models were compared by conducting an ultimate load test. The responses of both bridge models were almost identical, except for the failure mode and the ductility index.