Effect of FRP confinement of boundary elements in slender RC shear walls

Concrete shear walls are the most commonly used systems to resist lateral loads due to earthquakes in high rise buildings. In recent years، seismic design methodologies have put more attention on limiting the maximum drift experienced by a structure during earthquake. Very large in-plane stiffness of shear walls and its role on redistribution of the lateral loads from columns to wall provide an excellent drift control. Nevertheless، Time expiring، structural damages and early code shortcomings cause unsuitable efficiency of existing structural walls against earthquake. Fiber Reinforced Polymer (FRP) materials have greatly used in strengthening and retrofitting of structural elements in recent years. The excellent features of FRP materials set them the first alternative in the strengthening projects. However، a glance on the previous studies shows that very limited analytical and/or experimental studies have been conducted on the FRP strengthening of the slender RC shear walls so far. In this paper، effect of FRP confinement of boundary elements in slender RC shear walls on the overall behavior of boundary elements is investigated. The finite element software is calibrated and verified using available experimental data. Nonlinear finite element analysis of reinforced concrete walls is performed using damage plasticity model and tension stiffening effects. Results of the current study show the superior effectiveness of strengthening FRP composite layers on ductile behavior of concrete shear walls