Nonlinear behavior of RC shear walls externally bonded with FRP sheets
ABSTRACT
Composite shear wall system considered in this paper refers to a Reinforced Concrete (RC) wall where Fiber Reinforced Polymer (FRP) sheets are externally attached to the wall. The results of an analytical and parametric study on effectiveness of using externally bonded FRP sheets have been investigated in this research in order to evaluate the capacity curves (Load-Displacement relationships) of composite shear wall system. Verification of control RC wall has been carried out by comparing the results of finite element model and available experimental data. In the strengthening procedure using CFRP sheets, shear and flexural strength would be increased by applying CFRP sheets with the fibers oriented in the vertical and/or horizontal direction. The CFRP sheets are applied in order to increase the pre-cracked stiffness, the cracking load limit (up to 35 percent), ultimate flexural capacity (up to 20 percent) and the total hysteretic response of RC walls. In this case, displacement ductility factors, energy dissipation and contribution of structure’s modes to lateral deformation are presented. Finally as a parametric study, results of using wrapped CFRP sheets around plastic hinge area of wall indicated not only enough shear strength which provides a ductile failure mode but confinement of concrete would lead to increase the total ductility of RC wall.