Seismic retrofit of infilled reinforced concrete frames with CFRP composites

Although the infill walls are not considered as structural members during design, the observations made after earthquakes have shown that they are important resources of strength, stiffness and damping under lateral loads. Preventing premature damage of infill walls during earthquakes by keeping them in their locations can help the structure maintain its lateral strength, stiffness and damping characteristics, as well as vertical strength. In this study, six reinforced concrete frames, two bare, two infilled and two with CFRP retrofitted infill walls, were tested under constant vertical load and reversed cyclic lateral loads. Test data were evaluated in terms of strength, stiffness and failure mechanisms and it is concluded that retrofitting of infill walls by applying CFRP composites in diagonal directions, provides significant enhancement in lateral strength and stiffness.