Modeling of Shear-Critical Reinforced Concrete Structures Repaired with Fiber-Reinforced Polymer Composites

Abstract

This paper describes a study in which finite-element (FE) analysis procedures were used to predict the behavior of a reinforced concrete (RC) frame shear strengthened with fiber-reinforced polymer (FRP) composites. Details are presented of the numerical techniques used to represent the RC frame, the FRP, and the bond properties between the FRP and the concrete. The FE analysis is performed using a two-dimensional nonlinear FE analysis program based on the disturbed stress field model. To augment verification studies undertaken with beam specimens previously tested, a large-scale RC frame with one-span and two-story height was constructed and tested under lateral load conditions. The frame was first heavily damaged in shear, repaired with FRP wrap, and then subjected to a regime of reversed cyclic loads. A detailed comparison is carried out between analytical and experimental results for the hysteretic response, damage mode, crack pattern, and deformation of the frame. It is concluded that reasonably accurate simulations of the behavior of FRP-repaired shear-critical structures can be achieved through finite-element modeling.