CFRP Rod Panel Retrofit of Impact Damaged RC Bridge Girders

Impact of over-height trucks can cause considerable damage to concrete bridge girders. CFRP rod panels (CRPs) have emerged as an effective method of externally strengthening concrete structures. Both exterior beams of a reinforced concrete bridge over southbound Interstate 71 (I-71) in Kentucky were damaged due to an over-height truck impact. Two of fiveNo. 36 rebar (Diameter = 35.8mm, Area= 1006 mm(2)) in the bottom mat of each exterior beam was severely bent due to the impact. In addition, shear reinforcing bars in the vicinity of the impact were cut-off. CRPs were deployed to replace the load carrying capacity lost due to the damaged rebar. CRPs were chosen due to their modular construction capability, allowing the retrofit construction to be carried out using a smaller construction crew, and utilizing only a single lane closure on the interstate highway. CRP 195, with CFRP rods of 3.96-mm diameter, having a capacity of 870 kN per 300 mm width of panel, were selected for the flexural strengthening. Triaxial braided CFRP fabric (0 degrees, +/- 60 degrees) was selected for shear strengthening and served as containment of crushed concrete in the event of future over-height impacts. CRPs were found to be an excellent choice for the retrofit of impacted RC bridge girders, especially over multi-lane highways.