Three Caltrans-owned bridge overpasses in central California were found to have columns deficient in shear capacity. As an innovative alternate to steel jacketing, the prequalified Tyfo® system pioneered the use of fiber reinforced polymers for wrapping bridge columns since the late 1980s.
Fibrwrap Construction, the certified installer of the Tyfo® system, was selected to perform repairs on the spalled and unsound concrete at all three locations by applying the carbon-composite Tyfo® SCH-41 system to the rectangular columns to provide the full shear confinement required. Because the shear deficiency extended the full height of the columns, it was necessary to excavate down to the footings. Scaffolding was erected to allow access to the full height for the FRP wrap. The columns were then painted with a UV finish coat, Tyfo® U, to match the existing structure and add a protective coating to improve aesthetics. The solution saved Caltrans both time and money when compared to standard concrete steel jacketing, while achieving the structural strength needed to meet Caltrans’ needs.