REPAIR AND STRENGTHENING OF RC SHEAR WALLS USING EXTERNALLY- BONDED FRP SHEETS

摘要

This paper discusses the experimental results and preliminary analytical findings of a comprehensive, multi-phase experimental study for the seismic strengthening and repair of reinforced concrete (RC) shear walls using externally-bonded carbon fibre tow sheets. In the first two phases of the study, the enhancement of the flexural capacity and stiffness of slender shear walls is investigated. In Phase 3 of the program, the effectiveness of using externally-bonded carbon fibre tow sheets to increase the shear strength of eight slender and squat shear walls specimens with insufficient shear reinforcement and lap splices at the plastic hinge region is addressed. The experimental results from phases 1 and 2 show that the FRP flexural enhancement scheme in slender shear walls is successful in recovering (in repair applications) and increasing (in strengthening applications) the initial stiffness and the ultimate load carrying capacity of the test specimens, while at the same time maintaining ductile response behaviour and avoiding brittle shear failures. Preliminary analytical studies conducted in phase 3 of this study show a satisfactory performance of the carbon fibre system in eliminating the brittle shear mode of failure in walls with insufficient shear reinforcement and lap splices.