Seismic Resistance of Strengthened Reinforced Concrete Walls by Thick Jacketing

This study investigated the seismic resistance of thin, lightly reinforced walls strengthened in the out-of-plane direction by thick jacketing. To connect the thin existing wall and thick strengthening jacket, a tee shear connector consisting of one T-shaped steel section and several dowel bars and anchor bolts was used. Cyclic tests of four jacketed wall specimens were performed under out-of-plane lateral loading. The tests showed that the strength of the strengthened walls by thick jacketing was significantly enhanced. During the initial behavior, the tee shear connector performed well, not only as the shear connector; but also as the flexural tension reinforcement. However: as concrete damage increased during repeated load cycles, band failure occurred early in the tee shear connector under flexural tension. The flexural strengths of the strengthened walls by thick jacketing were computed based on full and partial composite action of the tee section, and the bond and shear resistances of the tee shear connector were estimated in accordance with the provisions of ACI 318-19.