Seismic Retrofit of Reinforced Concrete Frames with Filled Masonry Materials Using Fiber Reinforced Polymers

They typically behave brittle and have little or no ductility and are susceptible to various forms of damage such as invisible cracking, corrosion, and ultimately total destruction. This behavior is a major hazard during earthquakes, and this weakness in seismic performance has posed a major challenge to designers. Seismic retrofitting by adding structural frames or shear walls is impractical and very costly, and faces specific limitations in some buildings. Other retrofitting methods such as grouting, installation of reinforcing steel, prestressing, jacketing, and various surface reinforcement methods significantly increase the mass and stiffness of the structure, and as a result, impose higher seismic loads on the structure. These methods require skilled labor and disrupt the natural functioning of the building. These methods are referred to as "classical" methods of reinforcement. One of the new methods that has attracted the attention of industrialists in recent years is the reinforcement of existing buildings using composites. Much research has been conducted in this field and preliminary regulations have been prepared for their use. Composites were initially used for military applications and the aerospace industry, but with the decrease in price, these materials have attracted the attention of practitioners and industrialists in many industries due to their characteristics such as low weight and very high tensile strength, resistance to atmospheric conditions, etc. The use of fiber-reinforced polymers is a valid alternative reinforcement method due to its low thickness, high strength-to-weight ratio, high hardness, and easy application.