Response of RC Frames Strengthened by RC Infill Walls: Experimental Study

The experimental results of a research program on the response of 1/3-scale reinforced concrete infilled frames are presented and evaluated. The main objective was to assess the seismic performance of RC frames infilled with a cast-in-place RC wall designed according to the Greek code for retrofitting existing buildings. Seven infilled RC frames with a height-to-length wall aspect ratio hw/lw=0.58 were subjected to cyclic horizontal excitation. The parameters of the experimental study included the infill-to-frame method of connection along the horizontal and/or vertical interfaces and the anchorage length of the shear connectors placed along the interfaces. The columns of two of the infilled frame specimens were strengthened by a closed RC jacket. The presence of the RC wall resulted in a significant increase of the ultimate strength, in-plane stiffness, energy dissipation, and, to a certain extent, higher ductility. Specimens with jacketed columns appeared to have the best response.