Retrofitting of Defected Closure Strips for Full-Depth Precast Concrete Deck Slabs Using EB-CFRP Sheets

AbstractFull-depth precast deck panels are commonly used in RC bridges in order to speed their construction. In this study, two configurations of the closure strip between precast slab panels were proposed and filled with either nonshrink grout or ultrahigh-performance strain-hardening cementitious composite (UHP-SHCC) material. The proposed closure strips were strengthened by externally bonded carbon fiber–reinforced polymer (EB-CFRP) sheets in order to compensate for the drawback associated with decreasing the amount of connected steel reinforcing bars required to transfer bending moment between both panels. Twelve specimens divided into three groups were cast and tested under short-term nonreversal repeated patch loads simulating the wheel load at the central joint. Test results revealed that the UHP-SHCC filling material enabled the connected panels to exhibit more ductile behavior compared with panels using nonshrink grout. On the other hand, the CFRP-strengthening sheets for the first configuration of the closure strip failed to allow the CFRP-strengthened connected specimen to restore the ultimate capacity of the unstrengthened monolithic specimen. However, the second configuration of the closure strip using UHP-SHCC filling material enabled the connected panels to restore the lost capacity and outperformed it by about 14% compared with the unstrengthened monolithic specimen.