Dept. of Civil Engineering, Isfahan University of Technology (IUT), Isfahan, 84156-83111, I. R. of Iran
Concrete shear walls are the most prevalent structural systems resisting lateral loads due to earthquakes in high-rise buildings. Very large in-plane stiffness of shear walls provides an excellent drift control in the structure. However, structural damages and early code shortcomings threaten the efficiency of existing structural walls against earthquake. Recently, fiber reinforced polymer (FRP) materials have been used considerably in strengthening and retrofitting of structural elements. High tensile strength and excellent tensile modulus along with other unique features of FRP materials make them the first alternative in the strengthening projects. However, the literature shows that few analytical and/or experimental studies have been conducted on the strengthening of slender reinforced concrete (RC) shear walls with FRP materials so far. In this paper, the effect of strengthening of boundary elements in slender RC shear walls with FRP on the overall behavior of shear walls is investigated. Nonlinear finite element is used to analyse the RC walls, using damage plasticity model and tension stiffening effects. Results of the current study show that applying FRP sheets vertically on the lateral faces of the boundary elements causes the load-displacement curves of the strengthened walls to have a larger load carrying capacity up to 20% compared to that of wall specimens without FRP strengthening. Furthermore, applying the FRP sheets on the boundary elements only in the plastic hinge region of wall can improve the wall load carrying significantly.